The commands for basic control of the Dpi Oslo Mobile are generated by the app. A correct connection with the smartphone is therefore mandatory. By the way, it worked for me (iPhone 6s) right away :-)
The "toy" is ingenious and opens up completely new recording possibilities.

Have the same problem

Apparently, the sensor for mobile phone detection (whether the mobile phone is in the holder) does not work correctly if it does not have a metal back. However, the smartphone detection can be switched off in the Android app (setting "Phone Sensor" or similar).

I had this problem myself with the Galaxy S7, but it can be completely eliminated by changing the setting.

I had to download the app first, then it worked fine

Exactly as Anonymous answered. You first have to download the app (DJI Go) and "Authorise" the product, you also have to register/login there, after the process is complete the device will automatically turn on. I struggled with this for an hour myself. By the way, the app is a failure in terms of stability!