The iPhone 6S and 6S Plus were released in September 2015, as the successors to the iPhone 6 and 6 Plus. While the two may look alike at a glance, the newer models bring some significant upgrades and new features.

One of the most noticeable differences is the new color option. While the iPhone 6 and 6 Plus came in silver, gold, and space gray, the 6S and 6S Plus added a new rose gold color to the lineup.

The phones also utilize a stronger aluminum and a more durable glass, making them less prone to damage from drops and scratches.

Perhaps the most significant upgrade is the use of 3D Touch technology. This feature allows the screen to recognize how hard the user presses it, yielding new ways to interact with apps and notifications. For example, a user can use 3D Touch on an app icon to open a shortcut menu, or press on a notification to view its contents without opening the app.

The camera on the 6S and 6S Plus has also been improved, with a higher-resolution sensor and the ability to record 4K video. Additionally, the phones feature “live photos,” which capture a few seconds of video along with every still photo to create a more immersive memory.

The processors in the 6S and 6S Plus have been upgraded, making the phones faster and more efficient than their predecessors. The devices also come with the updated iOS 9 software, featuring improved Siri functionality, new keyboard options, and a redesigned Notes app.

While the iPhone 6S and 6S Plus may share many similarities with their predecessors, the new features and upgrades make them a significant improvement. The 3D Touch technology and improved camera capabilities alone make the 6S and 6S Plus a worthy upgrade for iPhone users.