Although not a prominent or widespread issue, some users do face this issue where Safari crashes or freezes on their iPhones and iPads running iOS 7. This appears to be an iOS-specific issue and most users are on older iDevices running iOS 7.
Obviously, this could mostly be a processing/memory/RAM issue. And one particular fix appears to work for a lot of people. Let's try that on your iPhone/iPad and see if it troubleshoots the problem for you.
Here's How to fix Safari crashing/freezing on iOS 7 on Your iDevice
Step 1: Clearing iCloud Data
- Open the Settings app
- Tap on iCloud
- Disable the switch for Safari
- You will be asked to confirm the change.
Step 2: Clearing Safari Cache/History
- Head back to the Settings app
- Scroll down and tap on Safari
- Tap on Clear Cache and Clear History to clear both of them. Confirm when asked to.
Step 3: Check
Try opening many webpages in multiple tabs to see if Safari stutters or freezes as before. Usually, since data is cleared, things should be fine and smooth now. However, in case Safari crashes again, you might have to resort to a hard-reset/soft-reset/restore routine.
Finally, when things are back to normal, you can re-enable iCloud's Safari switch to get back all bookmarks, reading lists and iCloud tabs that are open on other devices.
Make sure you don't let a lot of tabs running. Tabs accumulate over time if you don't routinely close them. You can swipe them to the left/right to close them or you can also follow this handy tip to close all tabs at once.
One other thing to note is that the Reading List (which contains links shared by the people you follow on Twitter) is available for reading offline. This can eat up some of the memory too so you've got to clear the cache every once in a while if you want to keep things empty/clear.