On iPhone 6s/6s Plus or earlier: Hold down the home button and the side/top button at once until the screen goes black and the Apple logo shows up on the screen.

On iPhone 7/7 Plus: Press and hold the side button and the volume down button simultaneously until you see the Apple logo on the screen.

After that, press and hold the side button until the Apple logo appears on the screen. Then, press and quickly release the volume down button.

On iPhone 8 or later: Press and quickly release the volume up button.

So, make sure the app you are trying to install on your watchOS device is compatible. There are still quite a few popular apps like WhatsApp that are yet to be available for Apple Watch. The very first thing that you should check out when faced with the app installation problem is compatibility. To resolve the issue, we are going to look into each possible cause and try some viable fixes.

Incompatibility, cluttered storage, and miscellaneous software glitches are also responsible for the app installation issue on your watchOS issue.

While a poor internet connection is the main reason why apps often fail to install on Apple Watch, there are other bottlenecks that you need to keep in mind. Erase Your Apple Watch And Repair Your Smartwatch to iPhone.Update Software on your Apple Watch and iPhone.Force Restart Your Apple Watch and iPhone.Make Sure to Download One App at a Time.Turn Off/On Cellular/Wi-Fi and Bluetooth (Toggle Bluetooth, WiFi, and Cellular Networks).Turn On/Off Airplane Mode (Toggle Airplane Mode).

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