"The" Swiss made secure messaging app (which already has brand recognition and some meaningful adoption within Switzerland) is Threema (no affiliation, and I'm using Signal - just comparing to Threema because "Swiss made" seems to be what this app is trying to make their main selling point).

This app has "1,000+" installs on the Play store (Threema: "1,000,000+"), and doesn't use phone numbers as IDs, i.e. it's only useful if you for some reason want to migrate all your friends to a brand new chat app that nobody else has heard about, and that has no really unique selling points, and thus little chance of building meaningful network effect (which is critical for chat apps, because a chat app without people to talk to is useless). As a result, it seems unlikely to be successful and thus unlikely to be supported (or exist) long term.

It seems to be a poorly thought out attempt to jump onto the wagon train far too late and get users trying to flee WhatsApp. Due to the network effect, adding choice is likely to help only the incumbent (WhatsApp) by making it harder for any of the alternatives to reach critical mass.

The crypto design is also highly questionable: They say they're using "SALSA 20", which is a low level primitive (comparable to e.g. AES), not a complete protocol. Advertising primitives shows little understanding of the actual problems in cryptographic practice, and thus a significant risk that not enough work went into designing the protocol around it, resulting in something that is insecure overall.