[ps67]

Sadly there are few ereader that can handle ACSM files directly, without needing Adobe Digital Editions. I know that Pocketbook can do it because I own it. You only need a account.

But of course I won't advice You to buy a ereader for that reason because You already use a tablet and You don't need a eink device.

I am not expert of Android app (I image that the tablet uses Android) but: does it exist a reader app that can handle ACSM files directly without ADE? You could explore that possibility.

If there is not such app You can try to install ADE trough Wine or to buy a old Kindle for the lowest price You can, but pay attention to the black list because otherwise You won't be able to register it on Your Amazon Account.

Edit: of course You can also install the kindle app on You reder and buy it from amazon. The purchase of a Kindle is to get rid of DRM.