If you're getting the error message 'insufficient storage available', you need to free some storage space on your phone.
Before going into troubleshooting, first check how much space you have left on your SD card.
To check your available memory, go to "Settings" > "Storage"
On most Android devices you will immediately see some sort of indicator of how much space you really have on your device.
Now, here are several ways to solve this error:
- Uninstall unused apps - The easiest way to free up storage space on your Android device is to get rid of the largest apps. Go to Settings, select Apps, under Downloaded tab press the menu (three vertical dots), and sort apps by size. This will enable you to identify apps which take up most of your storage space and to get rid of them.
- Delete the app cache - If your phone won't allow the installation of Photomath, you need to manually go through deleting the cache for each app. Go to Settings, select Apps and then the app you want to clean up, and then press Clear Data.
- Do a hard reboot on your device - see if that solves the problem.