Problem: We are experiencing that many of you have very low phone memory, and this can cause the app to crash - or prevent you from being able to download the app.
1. Delete caches from your apps. When dealing with apps, bear in mind that the app itself, its data, and its cache all add up to the total space used by the app. For example, if you have Spotify installed and you’ve cached lots of music offline, Spotify may be using over 1 GB of space. Many of the bigger apps like Facebook, Twitter, Instagram e.t.c uses a lot of space to store your caches.
Go into your phone settings and go over your bigger apps, to delete the caches to free up some space. If poking through each and every app looking for cached data to clear sounds like a chore, there’s an easy way to clear all cached app data in one single swoop. Tap Settings > Storage > Cached data, then tap OK in the confirmation window.
If you need more instructions, go to this link; https://www.androidcentral.com/how-and-when-clear-app-cache-or-data-android
Or view the Video below in solution 2.
2. On android phone, there is also a possibility to move your apps from the phone's internal memory to the SD card. This will free up space on your phone.
3. Clean up the Downloads folder
Just like on a PC or a Mac, your Android device has a Downloads folder (or Files on Pixel and some Oreo phones). It’s a favourite hideout for miscellaneous junk files downloaded from the Web or by your various apps.
Open the app drawer and tap Downloads or Files to see what’s lurking inside. Tap the three-line menu icon in the top corner of the screen and sort the list of downloads by size, then take a look at what’s hogging the most storage space. If you see anything you don’t need, tap and hold the file to select it, then tap the Trash button.
3. You might also have to delete some photos or video's from your phone or move them to your cloud storage to free up some space. If you don't have a cloud service, you can get this from
https://www.google.com/photos/about/ (this is free)
Download and use any of these services to back up your photos and videos. This way, your pictures and video's will be backed up, you can always access them, but you don't have to fill up your phone storage.
For more tips on clearing space on your phones, check out these links;