Apple’s latest pair of smartphones — the iPhone 6s and iPhone 6s Plus — bring more of an evolutionary change to the iPhone line, as opposed to revolutionary. While Apple definitely boasts a loyal fan base, as illustrated by the record 13 million new iPhones sold on its launch weekend, and a popular app marketplace, many Android fans feel Cupertino is simply playing catch up to the innovations of Samsung and other smartphone makers supporting Google’s mobile platform.

In fact, one more esoteric feature of the recently introduced iOS 9 is actually causing customers to use up the monthly data allowance from their wireless account — even on their home network.

Apple iPhone 6s

Let’s take a closer look at this issue as well as the features of Apple’s new iPhone 6s.

iPhone 6s and iPhone 6s Plus Features

The most intriguing new feature of the two new iPhones is something called 3D Touch. Essentially a pressure sensitive touchscreen, it allows users to perform new interface tricks provided the app in use supports 3D Touch. Most apps leverage the feature to pop up dialog boxes when a user presses on the screen — similar to the venerable right mouse button click in Windows.

The applications for 3D Touch for gaming, art apps, and the robust iOS music community are endless. Here’s hoping Apple introduces the feature in the next line of iPads. Touchscreen price considerations are probably the main reason the iPad Pro doesn’t support 3D touch.

Other new features of the iPhone 6s are primarily focused on technology. A faster processor and better camera resolution — including support for 4K video recording — highlight the improved specs. Apple usually saves more important upgrades for a new version number, so expect the iPhone 7 to be a bigger jump in functionality compared to the recently released model.

Watch Out for iOS 9’s WiFi Assist Feature

The new iOS 9 WiFi Assist feature garnered some bad publicity for Apple, when users noticed extraordinarily high data charges after installing the iOS upgrade. It seems WiFi assist switches to a cellular signal if it feels the WiFi connection isn’t strong enough. This is another good reason to regularly perform a speed test to ensure your home Internet (or hotspot when traveling) service is up to snuff.

Apple defaults WiFi Assist to on, so you simply need to go to your Settings app and find the WiFi Assist toggle under the Cellular (sometimes called Mobile Data) section and turn the feature off. If you don’t enjoy unlimited data, as most smartphone users, leaving the setting on could provide you with a nasty surprise when your next phone bill arrives.

With the interesting new 3D Touch feature and a pressure sensitive touchscreen combined with other incremental tech improvements, the iPhone 6s looks to be a winner for Apple fans. Just make sure you turn WiFi Assist off if you don’t have unlimited data.