App wont uninstall

Curious on what you have tried. I would double click to see what is in memory and get rid of everything by swiping it off, then close phone by holding on/off until it shows the swipe for shutdown icon and swiping it. Once apple disappears from resulting screen turn the phone back on holding the on switch till the apple shows. Once it comes back to normal see if the app icon is gone. If not, delete again. Good luck.

To do a reboot/soft-reset : press and hold both the sleep and home buttons for about 10 to 15 seconds (ignore the ‘slide to power off’), after which the Apple logo should appear and it should boot back up.

Have you tried rebooting the phone and then seeing how it shows in the App Store app ?

What else have you done ?