I have not seen this app mentioned here, but I find it really good. catima is foss discount and similar cards manager. Basically FOSS version of stocard.

It has no wearos app, but has some cool features as well. For me the main selling points were:

1. design is clean and is not filled with promotions and co
2. it does not require you to create a web account (and upload all cards there) just to move your data to a new phone like stocards does.