Where tapping the restoration button or reinstalling alone don't help, the following process can help with deep-seated problems (even issues not related to upgrades)
1) To get started, tap the Settings app on your phone's homescreen
2) Scroll down until you locate "Safari" and tap that option.
3) Scroll again till you see "Clear History and Website Data". Tap on it and follow any prompts that show up.
4) Go back to the main screen of the Settings app of your iOS device.
5) Now tap your name at the top of the Page, then tap "iTunes & App Store."
6) Tap your Apple ID and then sign out. (Don't forget your password!)
7) From here, go back to the first page in Settings, and then tap General. Next, tap iPhone Storage
8) You may have to wait a moment for the list to populate, however, scroll and locate MyRadar, tap the option and then select "Delete App".
9) Restart/Reboot your iPhone.
10) Go back and sign back in to iTunes & App Store.
11) Once signed in, reinstall MyRadar.
If you have in-app upgrades, you'll most likely need to restore your purchases. If that is the case, follow these quick steps below:
1) Open MyRadar and tap the Gear icon to open the settings menu.
2) Tap "Restore Previous Purchases" and follow the prompts!