It's impractical and will never happen.
If you want to measure noise levels from a mobile device - zero chance.
The first obstacle is the manufacturer.
Then the model.
Then the mic used in that model and if they used different mics.
Then you can get to business. But those barriers are not going to be breached easily.
THEN...
You need to deal with the specific mic used and deal with SPL vs. different weightings. Not going to happen.
Just get yourself a decent sound measuring device.
I might be off base there as I'm assuming a few things from what you've written. If so, ignore me.