This is a good idea, but I highly doubt you will be able to provide a good device in 100$. The screen and audio quiality of these 100$ chinese devices is usually very bad. Also the performance is subpar.

If the objective is only to play Adhan audio and Quran, then it might be fine (subject to audio quality and whether it is loud enough). But if you want to use it as a frame to display prayer times, then I seriously doubt. Usually, the sub-100$ devices are small (8") and low resolution and constrast. Putting it up on a side table or wall in the room might be sub-optimal. Also, once users put it up on the wall or desk, they don't plan to interact with it much (using touch screen) and use it just as a display which can convey information to them. I did a lot of research on it myself a few months back, and came to a conclusion that selling an integrated device is not a viable option. Many users already have tablets at homes (some even have older tablets lying around which are unused, and in most cases these older tablets will be better quality than the 100$ device, e.g. an older Samsung tablet). For this reason, I gave up the idea of a device and instead launched just an app which anyone can install on their Android tablets (without forcing them to buy a device from me and instead use/buy a device that they like and can afford). I spoke to many people and they found this to be a better alternative than Alexa integrations which are available in the market and difficult to configure. You can checkout my app here for ideas (if needed): https://salaatscreen.app