grain0615
I use Singpass as well, so far every (important) Singapore app works well for me, the only huge problem (not specific to Singapore) is if your company forces you to use Company Portal and they enforce play integrity API in their policies as well. This has resulted in someone that I know of having to purchase a $100 cheap Samsung just to comply with "company policies"
It is true that many apps are dependent upon Singpass app login, and the most major disruption to Singpass' functionality was back in July 2025 when GrapheneOS finally received the QPR1 update.
On 8th July 2025, Singpass stopped working on the 2025070800 release.
On 15th July 2025, Singpass started working again on GrapheneOS devices which had a previous login stored.
By 20th Aug 2025, Singpass setup on GrapheneOS was working again with the fix you pointed out.
Other than that Singpass has been working very well from 2022 till now.
I have contacted them myself during that period and I am not sure if its because of my feedback or numerous other users' complaint that resulted in the fix on 20th Aug 2025, but nonetheless nothing official was stated by them on supporting GrapheneOS through the hardware attestation API and as of today, they are still using play integrity API but unofficially "allowing" GrapheneOS to work by using the toggle provided by GrapheneOS.
My personal opinion is that govtech isn't deliberately trying to prevent GrapheneOS users from accessing Singpass, but for whatever reasons they are refusing to let go of Play Integrity API and other things like Native Code Debugging (ptrace). If they were truly trying to block GrapheneOS they could have technically implemented Play Integrity API properly in response to all the complaints by GrapheneOS users in Singapore long ago and block all non certified OSes but they have not done so yet.
I suggest that you write to govtech / Singpass' helpdesk asking them to consider following the guide here https://grapheneos.org/articles/attestation-compatibility-guide. If you're not satisfied with their reply, just go to your MP and relay your concerns, but its unlikely to change the official reply, but at least you registered your concerns with your MP directly. Here is a template that you can use as well, adapt it accordingly to your concerns.
https://github.com/PrivSec-dev/banking-apps-compat-report/issues/342
In anyways in the worst case scenario, if Singpass indeed stops working on GrapheneOS for a prolonged period of time, we still have access to SMS OTP + password login, but the digital ID and digital signing of documents such as for LPA / other types of applications will not be possible. In that case, the simple fix is to get a cheap pixel or samsung device and carry out what you need to do anyways, albeit that is very unfair to us, and no doubt less secure than just using GrapheneOS in the first place.