The Lenovo P2 works with Ant VR headset in its unique split-screen mode. The AntVR headset was the same same headset that is bundled with the Lenovo Vibe K4 Note in some countries. The headset is optimized for Lenovo's TheaterMax technology which have several options which one of them is a unique mode that splits the display into two halves, allowing you to consume any content, not just VR ones, like watching videos or playing any game with it. It also provides an enhanced 100-degree viewing experience. If you want to learn more about it, I recommend reading the two excellent reviews on gadgets.ndtv.com and on thequint.com.
I'm also adding an unboxing, setup and full review video by HowiSiT that gives you an inner look of this headset.
Regardless the compatibility. On gearbest.com I've read that the AntVR 3D VR glass is compatible with both Android and iOS smartphone with 4.5 to 6-inch displays, but to consume the content through the TheaterMax technology, you'll need the AntVR headset.
Anyways, it's great to have an option that allows you to just split the screen into two in order to consume any content up close. Just keep in mind that it's not turning any content into a stereoscopic view, but just let you view the content in large scale using the AntVR headset. So any app on your phone will work with it. For example, if you want to watch TV shows, live music concerts and movies on Netflix you can view content like you are viewing it on a very large screen. Even regular Android with a controller can work great with it..
In a video shared by C4ETech (see it below), the reviewer said that the TheaterMax technology doesn't work with Google Cardboard v1 because the distance of the lens from the handset which is probably an optical design that is requires to display the split content correctly. There is also the TheaterMax controller which you can use alongside the AntVR headset when playing Android games.
So if you find this feature useful and plan to use it, you probably should look into buying the AnrVR headset