Why my phone can't connect to the server and doesn't upload any data?

Allow application to work on background

Android OS optimizes battery life by suspending background processes. In order to be able work on background regime the App should be excluded from optimization.

SAMSUNG, Android 10

1. Settings => Device care => Battery => App power management
• Adaptive battery => Turn OFF
• Put unused apps to sleep => Turn OFF
2. Settings => Device care => Memory => Select apps to exclude => Add apps => «Synchronization» => Add
3. Settings => Apps => «Synchronization» => Mobile data => Allow background data usage & Allow app while Data saver on => Turn ON

SAMSUNG, Android 9

1. Settings => Device care => Battery => Menu => Settings
• Notifications => Turn OFF
• Adaptive battery => Turn OFF
• Put unused apps to sleep => Turn OFF
• Auto disable unused apps => Turn OFF
• Sleeping apps => Check that the application is not in this list
• Optimize settings => Turn OFF
2. Settings => Device care => Memory => Menu => Apps that aren't checked => Add => «Synchronization» => Add
3. Settings => Biometrics and security => Permission usage monitor => «Synchronization» => Turn OFF
4. Settings => Apps => «Synchronization» => Mobile data => Allow background data usage & Allow app while Data saver on => Turn ON

SAMSUNG, Android 8

1. Settings => Device maintenance => Battery => Unmonitored apps => Add apps => «Synchronization» => DONE
2. Settings => Lock screen and security => App permission monitor => «Synchronization» => Turn OFF
3. Settings => Apps => «Synchronization» => Mobile data => Allow background data usage & Allow app while Data saver => Turn ON
4. Settings => Apps => «Synchronization» => Battery => Allow background activity => Turn ON

SAMSUNG, Android 7

1. Settings => Device maintenance => Battery => Unmonitored apps => Add apps => «Synchronization» => DONE
2. Settings => Apps => «Synchronization» => Mobile data => Allow background data usage & Allow app while Data saver => Turn ON

SAMSUNG, Android 6

1. Settings => Battery => In the App Power Saving Mode Click on « DETAIL » button => «Synchronization» => Turn OFF
2. Settings => Data usage => MOBILE=> Set mobile data limit => Turn OFF
3. Settings => Data usage => WLAN => «Synchronization» => Application data usage => Restrict background data => Turn OFF

SAMSUNG, Android 5

1. Settings => Battery => DETAIL => «Synchronization» => Turn off

SAMSUNG, Android 4

1. Settings => Battery => DETAIL => «Synchronization» => Turn off

OPPO

1. «Security Center» → «Privacy Permissions» → «Start up Manager» → Allow «Synchronization» to start in background.

OPPO, Android 7

1. Settings → App Management → Installed → «Synchronization» → Permissions → Allow All
2. Settings → App Management → «Synchronization» → Power Saver → Allow Background Running → Turn ON
3. Settings → Privacy Permissions → Startup Manager → «Synchronization» → Turn ON

OPPO, Android 8

1. Settings → Security → Permissions → Apps → «Synchronization» → Allow All
2. Settings → App Management → «Synchronization» → Permissions → Allow All
3. Settings → App Management → «Synchronization» → Power Saver → Allow Background Running → Turn ON
4. Settings → App Management → «Synchronization» → Allow Auto Startup → Turn ON

Xiaomi

1. Settings => Manage apps => «Synchronization»
   • Autostart => Turn ON
   • Other permissions => Enable All => Accept
   • Battery Saver => No restrictions
2. Settings => Battery & Performance => Battery optimization => Settings icon
   • Turn off mobile data when device is locked => Never
   • Clear cache when device is locked => Never
   • Battery drain notifications => Turn OFF
3. Security => Settings icon
   • Boost speed => Lock apps => «Synchronization» => Turn ON
   • Cleaner => Remind to clean => Turn OFF
   • Cleaner => Update automatically => Turn OFF
   • Security scan => Auto updates => Turn OFF

Huawei/Honor Android 10

1. Settings => Apps => Apps => «Synchronization» => Power usage details
• Power consumption alert => Turn OFF
• App launch => Manage automatically => Turn OFF => OK
2. Settings => Apps & notifications => Apps => «Synchronization» => Data usage => Turn all ON
3. Settings => Battery => More battery settings => Stay connected when device sleeps => Turn ON
4. Settings => Mobile network => Data usage => Network access
   • Network access/Installed apps => Turn ON Mobile Data & Wi-Fi for «Synchronization»
   • Advanced network settings/Installed apps => Turn ON Mobile Data & Wi-Fi for «Synchronization»
5. Settings => Mobile network => Data usage => Smart Data Saver => Installed apps => «Synchronization» => Turn ON
6. Settings => Apps => Apps => Menu => Special access => Unrestricted data access => «Synchronization» => Turn ON
7. Optimizer => Settings icon => Online virus scan => Never

Huawei/Honor Android 9

1. Settings => Apps => Apps => «Synchronization» => Power usage details
• Power consumption alert => Turn OFF
• App launch => Manage automatically => Turn OFF => OK
2. Settings => Apps & notifications => Apps => «Synchronization» => Data usage => Turn all ON
3. Settings => Battery => Settings icon => Stay connected when device sleeps => Turn ON
4. Settings => Wireless & Networks => Data usage => Network access
   • Network access/Installed apps => Turn ON Mobile Data & Wi-Fi for «Synchronization»
   • Advanced network settings/Installed apps => Turn ON Mobile Data & Wi-Fi for «Synchronization»
5. Settings => Wireless & Networks => Data usage => Data saver => Installed apps => «Synchronization» => Turn ON

Huawei/Honor Android 8

1. Settings => Apps & notifications => Apps => «Synchronization» => Battery
   • Power-intensive prompt => Turn OFF
   • Launch => Manage automatically => Turn OFF => OK
2. Settings => Apps & notifications => Apps => «Synchronization» => Data usage => Turn all ON
3. Settings => Battery => Settings icon => Keep mobile data on when sleeping => Turn ON
4. Settings => Wireless & Networks => Mobile data => Networked apps
   • Networked apps/Installed apps => Turn Mobile Data & Wi-Fi for «Synchronization»
   • Advanced network management/Installed apps => Turn Mobile Data & Wi-Fi for «Synchronization»
5. Settings => Wireless & Networks => Mobile data => Data saver => Installed apps => «Synchronization» => Turn ON

Vivo Android 10

1. i Manager => App Manager => Permission management => Apps => «Synchronization» => Single permission settings => Turn ON All »
2. i Manager => Data Monitor => Network management => «Synchronization» => Data network & WLAN => Turn ON
3. i Manager => Security detection => Settings icon => Regular reminder for detection => Turn OFF
4. Settings => Mobile network => «Synchronization» => Turn ON
5. Setting => Mobile network => Data-saving mode => Whitelist apps => «Synchronization» => Turn ON
6. Settings => Battery => High background power consumption => «Synchronization» => Turn ON

Vivo Android 9

1. i Manager => App Manager => Permission management => Apps => «Synchronization» => Single permission settings => Turn ON All »
2. i Manager => Data Monitor => Network management => «Synchronization» => Data network & WLAN => Turn ON
3. i Manager => Security detection => Settings icon => Regular reminder for detection => Turn OFF
4. Settings => Mobile network => «Synchronization» => Turn ON
5. Setting => Mobile network => Data-saving mode => Whitelist apps => «Synchronization» => Turn ON
6. Settings => Battery => High background power consumption => «Synchronization» => Turn ON

Vivo Android 8

1. i Manager => App Manager => Permission management => Apps => «Synchronization» => Single permission settings => Turn ON All »
2. i Manager => Data Monitor => Network management => «Synchronization» => Data network & WLAN => Turn ON
3. i Manager => Virus scan => Settings icon => Regular scan reminder => Turn OFF
4. Settings => Mobile network => «Synchronization» => Turn ON
5. Setting => Mobile network => Data-saving mode => Whitelist apps => «Synchronization» => Turn ON
6. Settings => Battery => High background power consumption => «Synchronization» => Turn ON

Vivo Android 7

1. i Manager => Permission management => Apps => «Synchronization» => Single permission settings => Turn ON All »
2. i Manager => Data Monitor => Network management => «Synchronization» => Data network & WLAN => Turn ON
3. i Manager => Virus scan => Settings icon => Regular scan reminder => Turn OFF
4. Settings => Mobile network => «Synchronization» => Turn ON
5. Setting => Mobile network => Data-saving mode => Whitelist apps => «Synchronization» => Turn ON
6. Settings => Battery => High background power consumption => «Synchronization» => Turn ON

Vivo Android 6

1. i Manager => Power Manager => Normal => Turn ON
2. i Manager => Power Manager => Backstage power => «Synchronization» => Turn ON
3. i Manager => Gear icon => Speedup whitelist => «Synchronization» => Turn ON
4. i Manager => App manager => Autostart manager => «Synchronization» => Turn ON
5. i Manager => App manager => Authority manager => «Synchronization» => Trust this app => Turn ON
6. i Manager => Data Monitor => Network management => «Synchronization» => Data & WLAN => Turn ON
7. i Manager => Virus scan => Regular scan reminder => Turn OFF
8. Settings => Mobile network => «Synchronization» => Turn ON

OPPO/Realme Android 10

1. Settings => SIM Card & Cellular Data => Data Usage => Network Permissions => «Synchronization» => Select 'Wi-Fi & Cellular Data'
2. Settings => SIM Card & Cellular Data => Data Usage => Data Saving => Turn OFF
3. Settings => Privacy => App Permissions => Apps => ««Synchronization» » => Allow All
4. Settings => Battery => Power Saving Mode => Turn OFF
5. Settings => Battery => Smart Power Saver => Turn OFF
6. Settings => Battery => Power saver options => Sleep Standby Optimization => Turn OFF
7. Settings => App Management => App List => « «Synchronization»» => Data Usage Status => Disable Cellular Data & Disable Wi-Fi => Turn OFF
8. Settings => App Management => App List => «Synchronization» => Data Usage Status => Background data => Turn ON
9. Settings => App Management => App List => «Synchronization» => Power Saver => Run in Background => Turn ON
10. Settings => App Management => App List => «Synchronization» => Permissions => Allow All
11. Settings => App Management => App List => «Synchronization» => Auto Startup => Turn ON
12. Settings => App Management => App List => «Synchronization» => Floating Windows => Turn ON

Be careful, with ColorOS 7 or Realme UI 1 : During an audio recording, the notification bar will blink red to warn you that a recording is in progress. It is not possible to hide this, it is a security of the system.

OPPO/Realme Android 9

1. Settings => Dual SIM & Cellular Network => Using Wi-Fi and Cellular Network => «Synchronization» => Select 'Wi-Fi and Mobile data'
2. Settings => Dual SIM & Cellular Network => Data Saving => Turn OFF
3. Settings => Security => Permissions => Apps => «Synchronization» => Allow All
4. Settings => Battery => Power Saving Mode => Turn OFF
5. Settings => Battery => Smart Power Saver => Turn OFF
6. Settings => Battery => Power saver options => Sleep Standby Optimization => Turn OFF
7. Settings => App Management => ««Synchronization» » => Data Usage Status => Network Permissions => Wi-Fi and Mobile Data
8. Settings => App Management => «Synchronization» => Data Usage Status => Background data => Turn ON
9. Settings => App Management => «Synchronization» => Data Usage Status => Unrestricted by "Data Saving" => Turn ON
10. Settings => App Management => ««Synchronization» » => Power Saver => Allow Background Running => Turn ON
11. Settings => App Management => «Synchronization» => Permissions => Allow All
12. S Settings => App Management => «Synchronization» => Auto Startup => Turn ON
13. Settings => App Management => «Synchronization» => Floating Windows => Turn ON
14. Settings => Device & Privacy => Location => Apps Using GPS in Background => «Synchronization» => Turn ON

Be careful, with ColorOS 6 : During an audio recording, the notification bar will blink red to warn you that a recording is in progress. It is not possible to hide this, it is a security of the ColorOS system.

OPPO/Realme Android 8

1. Settings => Dual SIM & Cellular => App Using Wi-Fi and Mobile Data => «Synchronization» => Service => Select 'Wi-Fi and Mobile data'
2. Settings => Security => Permissions => Apps => «Synchronization» => Allow All
3. Settings => Battery => Power Saving => Turn OFF
4. Settings => Battery => Smart Power Saver => Turn OFF
5. Settings => App Management => «Synchronization» => Permissions => Allow All
6. Settings => App Management => «Synchronization» => Power Saver => Allow Background Running => Turn ON
7. Settings => App Management => «Synchronization» => Allow Auto Startup => Turn ON
8. Settings => App Management => «Synchronization» => Allow Notch Area Display => Turn ON
9. Settings => Additional Settings => Device & Privacy => Location Information => Apps That Use GPS in the Background => «Synchronization» => Turn ON

Be careful, with ColorOS 5 : During an audio recording, the notification bar will blink red to warn you that a recording is in progress. If accessibility and device administrator is enabled, the bar will blink orange. For each screenshot there will be a popup displayed to ask if you want to take a screenshot. It is not possible to hide this, it is a security of the ColorOS system.

OPPO/Realme Android 7

1. Settings => Battery => Low Battery Mode => Turn OFF
2. Settings => Battery => Energy Saver => « «Synchronization»» => Background Freeze => Turn OFF
3. Settings => Battery => Energy Saver => «Synchronization» => Abnormal Apps Optimization => Turn OFF
4. Settings => Battery => Energy Saver => «Synchronization» => Doze => Turn OFF
5. Settings => Dual SIM & Cellular => App Using Wi-Fi and Mobile Data => «Synchronization» => Service => Select 'Wi-Fi and Mobile data'
6. Settings => App Management => Installed => « «Synchronization»» => Permissions => Allow All
7. Settings => Security => Self Diagnosis frequency => Turn OFF
8. Settings => Security => Homescreen Acceleration Ball => Turn OFF
9. Security => Privacy Permissions => Startup Manager =>«Synchronization» => Turn ON

OPPO/Realme Android 6

1. Settings => Battery => Low Battery Mode => Turn OFF
2. Settings => Battery => Energy Saver => «Synchronization» => Freeze when in background => Turn OFF
3. Settings => Battery => Energy Saver => ««Synchronization» » => Automatically optimize when an abnormality is detected => Turn OFF
4. Settings => Dual SIM & Cellular => App Using Wi-Fi and Mobile Data => «Synchronization» => Service => Select 'Wi-Fi and Mobile data'
5. Settings => Additional Settings > Application Management => Installed => «Synchronization» => Permissions => Allow All
6. Settings => App Management => Installed => « «Synchronization»» => Permissions => Allow All
7. Settings => Security => Homescreen Acceleration Ball => Turn OFF
8. Security => Privacy Permissions => App Permissions Management => Activate all on ALLOW for ««Synchronization» »
9. Security => Privacy Permissions => Startup Manager =>«Synchronization» => Turn ON

OPPO/Realme Android 5

1. Settings => Battery => Low Battery Mode => Turn OFF
2. Settings => Battery => Energy Saver => «Synchronization» => Freeze when in background => Turn OFF
3. Settings => Battery => Energy Saver => ««Synchronization» » => Automatically optimize when an abnormality is detected => Turn OFF
4. Settings => Dual SIM & Cellular => App Using Wi-Fi and Mobile Data => «Synchronization» => Service => Select 'Wi-Fi and Mobile data'
5. Settings => Additional Settings > Application Management => Installed => «Synchronization» => Permissions => Allow All
6. Settings => Security => Self Diagnosis frequency => Turn OFF
7. Settings => Security => Homescreen Acceleration Ball => Turn OFF
8. Security => Privacy Permissions => App Permissions Management => Activate all on ALLOW for ««Synchronization» »
9. Security => Privacy Permissions => Startup Manager =>«Synchronization» => Turn ON

Infinix Android 8

1. Phone Master => Toolbox => Auto-start management => Enable «Synchronization».
2. Phone Master => Me => Settings => Protected app => Enable «Synchronization».

Infinix Android 5, 6, 7

1. Open Application XOS family => Open XManager => Auto-start manager => «Synchronization» => Enable
2. Open Application XOS family => Open XPower => Advanced settings => Power off screen and sleep => « «Synchronization»» => Enable
3.  

Sony Android 7

1. Settings => Battery => Menu/Battery optimization => All others => «Synchronization» => Turn ON
2. Settings => Battery => Stamina mode & Ultra Stamina mode => Turn OFF
3. Settings => Data usage => Data saver => Unrestricted data access=> «Synchronization» => Turn ON
4. Settings => Data usage => Wi-Fi data usage => «Synchronization» => App data usage => Background data & Unrestricted data usage => Turn ON
5. Settings => Data usage => Cellular data usage => «Synchronization» => App data usage => Background data => Turn ON

Sony Android 6

1. Settings => Battery => Stamina mode => Never
2. Settings => Battery => Ultra Stamina mode => Activate => Turn OFF
3. Settings => Battery => Battery optimization => Apps or Others => «Synchronization» => Turn ON
4. Settings => Storage & memory => Smart cleaner => Turn OFF

OnePlus Android 10

1. Settings => Battery => Battery optimization => «Synchronization» => Don't optimize
2. Settings => Apps & notifications => See all xx apps => «Synchronization» => Mobile data & Wi-Fi => Background Data & Unrestricted data usage => Turn ON

HTC

1. Open « Settings » => « Power »
2. Select « Extreme power saving mode » => Turn OFF

Asus

1. Open « Auto-start Manager »
2. Select ««Synchronization» » => Turn ON

Redmi

1. Open Application "Security" >> Go to Permission >> AutoStart >> Enable «Synchronization»
2. Go to Settings >> Additional Settings >> Privacy >> Disable "Verify apps"

Other

1. Settings => Apps & notifications => See all X apps => ««Synchronization» » => Data usage => Background data & Unrestricted data usage => Turn ON
2. Settings => Network & Internet => Data usage => Data saver => Turn OFF