You can use the Insta360 Nano with a modified adapter on an iPhone 5 (with limits), or iPhone 5S or iPhone SE. The adapter is inexpensive, and the modification takes less than 5 minutes. It also works with some smartphone cases.
Correction: it appears the Nano is not fully compatible with iPhone 5 - photo works, but there are errors when shooting video. iPhone 5S and SE have no issues. Thanks to Skip Hunt for bringing this to my attention!
The Insta360 Nano is a 360 camera designed for the iPhone 6 series and 7 series. It is one of the most affordable fully spherical 360 cameras and has very good video quality and excellent 360 livestreaming capability. (Here is my review.)
However, the Nano has a couple of compatibility issues: First, the Nano won't fit the iPhone 5 or iPhone SE. The Nano is curved to fit the curved edge of the iPhone 6 and 7 series, and can't fit the flat edge of the iPhone 5 or SE. Similarly, the Nano won't fit iPhones with protective cases.
Fortunately, the solution to both compatibility issues is simple, easy, and cheap. I used a lightning port extension adapter. This one looks identical to the one I got.
The adapter has to be shaved a bit using an ordinary disposable nail file. It takes only a couple of minutes.
According to reader Skip Hunt, it can be used on an iPhone 5 as well, but only for photos. With videos, the live view gets interrupted.
Please note that this is not an approved accessory for the Nano, so there's no guarantee it will continue to work - use at your own risk. FWIW, I was using iOS 10.2, Nano firmware 1.43, and app version 1.6.2.
Thank you very much to the reader who told me that the adapter works after modifying it. I'm really sorry I forgot who you are. 😭 Pls. message me so I can acknowledge you and thank you!