The situation when Internet connection The phone cuts off the moment you remove your finger from the lock button, a familiar occurrence for many smartphone users. The screen goes dark, the device goes into standby mode, and after a few minutes, file downloads stop, and messaging apps stop receiving new messages. This isn't a bug in a specific app, but rather a system behavior of the operating system designed to conserve battery life.
However, for those who download large files or are waiting for an important notification, this "saving" becomes a serious problem. Operating systems Android and iOS have different approaches to managing network modules during sleep, but the logic is similar: if the screen is off, it means the user is inactive, and the radio module's power consumption can be reduced. In this article, we'll look at how to keep your phone connected 24/7.
Reasons why Wi-Fi is disconnected on Android
The main culprit on devices running Android is an aggressive power saving policy. The system tries to extend battery life by disabling Wi-Fi module or putting it into sleep mode when the device's screen goes dark. This is the default behavior for most OS versions, starting with Android 6.0 and newer, where the Doze and App Standby algorithms are particularly strict.
Furthermore, the router itself may terminate the connection with a client that has not transmitted data for a long time, considering it "dead." If a short timeout is set in the router settings for DHCP leases or disconnecting inactive clients, the phone will lose network connection. It's also worth considering that some shells Manufacturers (MIUI, OneUI, ColorOS) have their own, even stricter power management rules that override the standard Android settings.
It's important to distinguish between a software glitch and a hardware problem. If Wi-Fi only disconnects after the screen goes dark and reconnects immediately after activating it, it's a software issue. If a full reboot of the smartphone is required to restore the connection, it could be a hardware issue. drivers or unstable operation of the network chip.
Power saving settings on Android
The first thing Android smartphone owners should check is their global Wi-Fi settings. In older versions of the system, there was an explicit "Turn Wi-Fi on during sleep" option, but in modern interfaces, it's often hidden or moved to the developer menu. You need to find the section responsible for this. Wi-Fi Preferences.
The second important aspect is the settings for the specific app. If you're not receiving notifications from Telegram or WhatsApp only when the screen is off, it means the system is "killing" the app's process to save power. Go to the battery settings, find the relevant app, and select "Unlimited" or "Don't save battery."
It's also worth paying attention to the "Adaptive Wi-Fi" or "Wi-Fi Assistant" feature. These algorithms can automatically switch you to mobile data if they detect an unstable Wi-Fi signal while the screen is idle. Disabling this feature often resolves the tearing issue.
- 🔋 Go to
Settings → Battery → Power saving modeand make sure that the "Performance" or "Balanced" mode is selected. - 📱 Log in
Settings → Applications → [Your application] → Batteryand remove background activity restrictions. - 📶 Disable the "Switch to mobile data" feature if it is enabled in the advanced Wi-Fi settings.
- ⚙️ In the developer menu, find the "Always keep Wi-Fi active" option and set it to "Always."
☑️ Check Android settings
iOS Specifics: Wi-Fi Assist and Background Activity
In the ecosystem Apple Things are a little different. iOS is famous for its optimization, but sometimes this plays a cruel joke. The function Wi-Fi Assist (Wi-Fi Assistant) is designed to improve connection quality, but it often causes the phone to ignore weak Wi-Fi and switch to LTE, especially when the screen is off and background processes require stability.
Another possible cause could be the "Cellular Data" setting for specific apps. If you've blocked an app from using mobile data, but the Wi-Fi signal in sleep mode is slightly weaker than the cutoff, iOS may simply disconnect without being able to switch. It's also worth checking your settings. Background App Refresh (Content Update), since without it, many applications stop working in the background.
On iPhones with Always-On Display (e.g., iPhone 14 Pro and newer), the situation may be different, as the screen technically doesn't turn off completely, but merely reduces brightness. However, iOS algorithms may still limit network activity for heavy tasks, such as downloading system updates or large files to iCloud.
⚠️ Attention: There's no single "Keep Wi-Fi On" button on iOS. The system automatically decides when to disconnect based on signal strength and user behavior. If the issue is critical, jailbreaking or using a third-party tweak may be the only solution, but this compromises the device's security.
Router Settings: Timeouts and DHCP
The problem may lie not with the phone, but with the router. Many routers have a function Green Wi-Fi or "Eco Mode," which reduces signal strength or turns off antennas if connected clients are inactive. When the phone's screen goes dark, traffic drops to zero, and the router decides the device is no longer needed.
It's also important to check your DHCP server settings. If the lease time is set too short (for example, 1 hour or less), and the phone doesn't renew the lease while in sleep mode, it loses its IP address. When the screen is turned on, the phone begins the process of obtaining an address again, which appears to be a disconnect.
It's recommended to check your router logs when the screen goes dark. If you see constant reconnections (Death/Disassociate), the router may simply be resetting the client due to security settings or overheating.
| Parameter | Recommended value | Impact on the problem |
|---|---|---|
| DHCP Lease Time | 1440 minutes (24 hours) | Increases the lifetime of an IP address |
| DTIM Interval | 1 or 3 | Buffered data delivery frequency |
| Beacon Interval | 100 ms | Standard network beacon interval |
| Green Wi-Fi | Disabled | Prevents power loss |
What is DTIM?
DTIM (Delivery Traffic Indication Message) is the interval at which the router notifies sleeping devices that data is available for them. If this value is too high, the phone may miss the data transfer and disconnect.
Driver issues and static IP
On Windows computers and some Android tablets, a common cause is the network adapter's power management settings. The system allows the adapter to shut down to save power, which leads to a complete loss of connection when it goes into sleep mode. This can be resolved through the Device Manager.
Find your Wi-Fi adapter in the list, go to Properties, the "Power Management" tab, and uncheck "Allow the computer to turn off this device to save power." This will ensure the module remains running, but may increase battery consumption by 5-10%.
Another method is to use a static IP address. Dynamically obtaining an address (DHCP) requires a constant exchange of service packets. If this exchange is interrupted, the connection is lost. A static address eliminates the need for this dialogue, making the connection more "sticky."
To set up a static address on Android, go to Wi-Fi settings, click on the gear icon for your network, select "IP Settings" and replace DHCP with StaticEnter an address that matches your network range (e.g. 192.168.1.150), gateway, and DNS.
Hidden factors: interference and overheating
Physical factors shouldn't be ignored. When the screen goes dark, the phone is often placed in a pocket, bag, or on a table, changing its position. If the Wi-Fi signal is weaker in these locations or there is interference from microwaves or Bluetooth devices, the module may not be able to maintain the connection.
There's also the issue of overheating. When actively downloading files, the processor and Wi-Fi module become hot. When the screen goes dark and the phone is placed in a case, heat dissipation deteriorates. Throttling occurs, the module reduces power or shuts down for protection, which the user perceives as a software glitch.
Check if your phone has a metal case or a magnetic ring for a car mount. Metal shields the signal, and the moment you stop looking at the screen and change your grip, the connection may be lost.
⚠️ Attention: Router settings interfaces and Android versions are constantly updated. The layout of menu items may differ from what's described. Search for keywords like "Power," "Sleep," "Eco," and "Battery."
Frequently Asked Questions (FAQ)
Why does Wi-Fi only turn off on the lock screen, but it works when it's on?
This is the operating system's default behavior to conserve battery power. When the screen is active, the system assumes the user is working and maintains maximum network performance. When the screen is locked, power-saving algorithms are activated, which may disconnect the connection or reduce the module's power.
Does setting a static IP address affect internet speed?
No, a static IP address does not affect data transfer speed. It only changes the way addresses are assigned to devices on the local network. However, it can improve connection stability by eliminating possible address conflicts or DHCP server timeouts.
Can antivirus block Wi-Fi in sleep mode?
Yes, some aggressive antivirus and firewall programs have a "Sleep Mode" or "Night Mode" feature that limits network activity to conserve resources. Check your security software settings and add exceptions for critical applications.
Will resetting network settings help?
Resetting network settings deletes all saved Wi-Fi passwords, Bluetooth settings, and VPN settings. This may help if the issue is caused by a software conflict or incorrect protocol configuration, but it won't resolve the problem if the hardware is power-saving.