I have the iPhone app. I have had it crash less than a handful of times. Yesterday it was timing out so I couldn't even open it. But, thankfully this morning it is back up on my phone.
As for iPhone apps. I usually live with it until an update comes out. Unless it is obnoxious then I delete it and upload again. Or, leave it off until an update comes out. Doing a hard reset my fix it if it is your phone that is messed up and not the app.