I personally use the JJC intervalometer for the a7R II/SII (Amazon). Here’s my review of it:
Here’s a video in which you’ll find timelapses I’ve shot with it:
https://www.youtube.com/watch?v=7z_Do6N7gI0
I don’t use or recommend the Sony time-lapse app for these reasons:
- I have three cameras, so I have to buy and install it on each of them…and any future cameras
- It drains battery to change settings in camera in the field.
- In bright sunlight, it’s hard to read off the LCD.
- I’ve found, and it seems miraculous, I can get more shots out of the camera by using the intervalometer than just the stock battery! The JJC runs for months on a pair of AA batteries.
Notes
There’s nothing wrong with the Sony app, if all you’re using is one camera and a couple of types of timelapses. It all depends on what you want to do.