Introduction
For the past couple of months, I have been battling an issue on my phone.
Each morning I start Outlook up and it hangs for a moment and then prompts me to sign into Microsoft 365. The same behaviour is seen with To-do and the office apps were not behaving as well as I would like and cache old data.
I have seen lots of other people experiencing the issue as well and a few other posts on Microsoft community sites asking for help.
Well, it occurred to me that I had set the Android developer mode, which might be causing the problem. I switched this off a few days ago and since then I have not been asked to re-sign into Outlook or any of the Microsoft 365 Apps. Additionally, my phone, not surprisingly is much faster!
I remember switching this one when using screen casting software to present my mobile in a presentation.
Here is how to switch it off
How to switch off Android Developer Mode
To switch off do the following:
- Open the settings app
- Scroll to the bottom of the settings app and choose System -> Developer options
- Disable the Developer options by toggling the switch to off.
Conclusion
I hope if you have this problem, it solves your issue.
Since switching this off I have not had the issue with Outlook or any of the other Microsoft 365 app asking to sign-in.
Please let me know if it does or does not via the comments.
Switching on Android Development
You can enable Android developer mode by doing the following:
- Open the settings app
- Scroll to the bottom of the settings app and choose System -> About phone
- Click on the build number seven times
- You will be asked to put in your pin number.
- The developer mode option is enabled and available by closing the Settings app and choosing Settings-> System.
Doy's Microsoft 365 and Azure Dev Blog 
Thank you, but sadly this does not seem to apply to phones made by manufacturers who create their own Android-based OS, such as OPPO which has have what they call Color OS based on Android and uses the same version number of the Android systen upon which they’re based. I have the Oppo A55s 5G running Color OSV12based on Android12. No developer mode option available to enable/disable.
Unfortunately, problems with the Outlook Android app persist and I’m on the verge of giving up on ever being able to use the app on my phone after it suddenly stopped loading anything (blank white screen). Uninstalling and reinstalling the app and trying to sign in is the next problem where one gets stuck in a loop after entering the email address and the p/w which then brings one back to the log-in screen once more…