Has anyone seen the S-pens SDK in the Play Store or galaxy apps store? What exactly is it for and even if I'm not developing any kind of modifications to the S-pen feature of Samsung phones can I download the app to enable an S-pen to be used with my phone?
My phone is a Galaxy A5 (2015)
This is the downloadable library for the Pen package, which is a part of the Samsung Mobile SDK. With the library installed, your application regarding SPen is able to use the latest Pen package features.
( Emphasis supplied)
So, no, you can't download the app and expect to have S pen enabled on your device, since it doesn't have S pen to start with. Quick search on XDA didn't show any mod / custom ROM which has S pen feature
S pen SDK that can be downloaded from OEM is for developers to develop applications using S Pen
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