Got an iPhone 6s and want to get more out of its 3D Touch feature? I've got 5 great tips for you.
Adjust 3D Touch's sensitivity
Start off by adjusting how sensitive you want 3D Touch to be. To do it, select Settings-->General-->Accessibility-->3D Touch. From the screen that appears, you can choose from LIght, Medium, or Firm. (The default is Medium.) To test out your new setting, use the 3D Touch Sensitivity Test at the bottom of the screen.
Peek and Pop in the Mail app
3D touch has two especially useful features --- Peek and Pop. Peek lets you preview the contents of something, such as a document or email, and Pop opens the item in its app. Mail is a good way to test out Peek and Pop. Press on an email and a preview of the message appears. Press it even harder and the email opens fully in the Mail app.
3D Touch is great for getting a quick preview of an address in Maps, without having to actually go to the Maps app. If someone sends you an address in an email, you might normally tap the address, which would send you to the Maps app. If you instead want to stay in Mail, but want a quick peek at the address on a map, press on the address and a map preview appears, while you're still in Mail.
Turn on the app switcher
iOS includes a handy app switcher that lets you flick through your recently opened apps. Normally you get to it by double-pressing the Home button. But you can also get to it by hard-pressing next to the lefthand edge of the Home screen, or while in many apps.
Take a quick selfie and more with the Quick Actions menu
Hard press an apps icon, and if it takes advantage of 3D Touch, up will pop a Quick Actions menu that lets you perform an action fast. For example, hard-press the Camera icon and you'll be able to choose from taking a selfie, recording a video, recording in slo-mo, or taking a photo.