Update your iPhone or your internet might go away

Folks with older iPhones need to update their devices with the latest software before Sunday.

the operating system “update is required to maintain accurate GPS location and to continue to use functions that rely on correct date and time including App Store, iCloud, email, and web browsing.”

The bottom line: You might not be able to get on the internet with old software.

The update is critical for iPhone and iPad products from 2012 and earlier:

-- iPhone 5 and iPad (4th generation) Wi-Fi + Cellular should be updated to iOS 10.3.4.

-- iPhone 4s, iPad mini (1st generation) Wi-Fi + Cellular, iPad 2 Wi-Fi + Cellular (CDMA models only), iPad (3rd generation) Wi-Fi + Cellular should be running iOS 9.3.6.

“This issue does not affect iPod touch or any iPad models that have Wi-Fi only,” according to Apple. “It also doesn't affect iOS devices newer than those listed above.”

If you're not sure which version your iPhone or iPad has, follow these directions:

1. Open the Settings app

2. Tap General, then tap About

3. Look for the number next to Software Version

If you do need to

, go to Settings > General, then tap Software Update.