If your iPhone runs iOS 7 or later, you can easily turn off auto app update on Wi-Fi or Cellular. To enable / disable auto app updates on iPhone, iPad and iPod Touch devices, do as follows:
1. Open the Settings application
2. Scroll down and find the iTunes & App Store option and tap to open it
3. Make sure the Updates button is toggled off, so your apps won't update automatically and have to update apps on iPhone manually.
Note that, if you worry about updating your apps using the SIM card internet connection, simply make sure the Use Cellular Data option is toggled off.