Tap the Update icon at bottom right of the screen.You can check for App updates, using the latest version of app is either way best practice for many reasons. Sometimes there might be issue with the current version of app and most of times developers fix it by releasing newer version of app. Now, once more press and hold 'Sleep/Wake' button for some seconds.

A slider will show up, swipe it to right.

Press and hold 'Sleep/wake' button for some seconds.

It was pretty frustrating, one of my friend suggested to Turn off my phone and power on again if apps won't open on iPhone 6 and I tied that which solved my problem. The very basic thing you can do is trying shut down your iPhone and booting it, I had iPhone 6 in past and I was dealing with the problem where my tumblr app won't open. People have reportedly solved their app crash issues or app not starting at all problems using the fixes given below. There are multiple things which can make your apps won't open on iPhone, ultimately these problems can be solved using different solutions. However you can try the below solutions to troubleshoot app crash problems. Main culprits for this problem are low memory, software issues, compatibility issues and buggy app itself. This kind of problem can be triggered due to many reasons, this guide will cover the methods which can fix apps not opening on iPhone problem. Sometimes your apps may misbehave or won't start at all, no matter ho many times you try to launch the app, it just won't open.

Fix Significant Locations iPhone Not Working.

Fix Photos Stuck on Preparing to Import from iPhone.

Backup iPhone 7/7 Plus with Broken Screen.

Find My iPhone Unable to Connect Server.

iMessage Needs to Be Enabled to Send This Message.

iPhone Keeps Connecting and Disconnecting from Mac.

Cydia Impactor Stuck on Generating Application Map.

On My iPhone Option Missing in Files App.

Data recovery cannot be completed, please restore.

Find My iPhone Must Be Turned Off Before iPhone Can Be Restored Error.

Can't Update iOS due to iCloud Restoring.

Fix Snapchat Not Working on WiFi/Mobile Data.

Fix iPhone Calendar Slow after iOS Update.

Fix People Album Not Populating on iPhone.

Stop Music from Automatically Playing On iPhone.

Facebook Messenger Video Call Not Working.

Iphone 6 kindle app sync failed