Following a battery replacement, strange things have happeded.!

Now I have a question or two. After installing a new battery, I've discovered that there is a problem. My phone appears to work normally until I try to open an app. This does not apply to the 'basic' apps for each phone or to 'settings'. Or to the clock and time display. It continues to works perfectly as a phone - receiving calls and allowing me to make calls - and all of the various sounds work correctly.

When I touch the icon of an app, the icon opens briefly then closes. No matter what I do, it will not stay open or do anything

When I go to the first screen to clear previously opened apps, the icons for those that did not open, still appear, and can be cleared normally by double clicking the Home button and touching the icon to close it.

Are you familiar with this problem? I think it might be a poor connection to one or two of the connectors inside the phone but which?

I'd like to fix this as I am unable to use most of my most useful apps, like flashlight, weather, etc. I have no problem with the iPod feature, Mail, Phone or Safari whose icons are in the bottom row. The camera still works correctly. But I get this open-and-close-immediately problem from the rest, including all Utilities, but not any of the top four icons for Messages, Contacts, Calendar or Clock, and oddly, the Travel GPS feature works fine.

I can only think that one or two of the necessary connectors have come adrift, but I can't spot the problem and don't know which connectors are likely culprits in this case. Solutions gratefully received.