I use iPhone 4 with ios7.recently i am facing a problem,when i open apps like whatsapp,instagram etc the notice comes saying connect to iTunes to use push notifications.my apple id is active on phone.any solution!?

Hello there, ajinkyab.

The following Knowledge Base article provides some great. practical steps for troubleshooting the issue you're describing:

iPad and iPod touch: Unable to use YouTube or Push notifications

http://support.apple.com/kb/TS3305

To use certain services, iTunes must download and install an authentication token on the device. Because iPad and iPod touch do not require an active Internet connection to activate, these tokens may not be downloaded and installed during initial setup.

You can resolve this issue by verifying that iTunes has an active Internet connection. Use the following steps:

1. Open iTunes on your Mac or PC.
2. Verify that your Mac or PC has an active Internet connection by accessing the iTunes Store in iTunes.
3. Connect your iPad or iPod touch to your Mac or PC.
4. After the sync completes, verify you can access YouTube.

This article also provides a great resource for troubleshooting apps installed on your iOS device:

iOS: An app you installed unexpectedly quits, stops responding, or won’t open

http://support.apple.com/kb/TS1702

Thanks for reaching out to Apple Support Communities.

Cheers,

Pedro.