Why won't it let me open the app?

Well, on my iPhone 4S I have downloaded an app called oovoo but it's not there and when I typed it again on the App Store it says open app but then it won't
Let me open it please help? Sorry x

I have oovoo it's really good app so your phone or only downloaded it wrong mine does this too with random apps if possible delete and redownload Or turn of your phone and turn it back on

  • Why won't the App store let me update my apps - Iphone 4s? After downloading the new software for the iPhone (iOS 6.1) it will not let me update my apps. I open up the app store on my phone and go to the update tab, and it remains blank (despite saying there's 7 updates). Does anyone know what to do? I have tried restarting my phone.
  • Why won't my twitter app open on my iPhone? I updated the twitter for iPhone app after I downloaded iOS7 and it was taking forever to update then when it updated it wouldn't let me open the app. I deleted it then reinstalled it and the app still won't open but all the other apps I updated do open. The twitter app does not open at all. Any help? What can I do?
  • Why won't my app store let me download apps? I just got my iphone 5 and it won't let me download any apps it keeps making me do security questions before i can download apps, but when i do it it says its timed out and to try again.
  • Why won't it let me buy an in app purchase? So, i have a jailbroken iphone, and it didn't come with the in app purchases. & my friend gave me a itunes card to buy it. It won't let me buy it, and i've already offically bought the game, instead it gives me an error message saying "to purchase an application change the terminal settings" I have no idea, what is wrong. & it would also tell me this when i had an ilegal version, from installous. So any help?