That is a huge loss for SailfishOS cumminity.

whatsapp not worth it. prefer using telegram. it's not banning users for 3rd party clients.

And what is the 3rd party client for Sailfish? Any chance it can be a next version of Mitakuuluu? Maybe from your hand? As the Mitakuuluu as 3rd party for WA was easier to use on my Jolla. I like to see a similar client for TG. I use both, WA and TG. I like TG better, if only for the availability of stickers.

Some people cannot afford to switch a chat service every two weeks. I am one of the fortunate old farts who has never reached the point of using Whatsit. Absolutely everyone I know uses Skype and nothing else, from the days before it was Microsoft. Telegram? What is that?

(The point being that some people may be stuck with Whatsit for the same reason I am stuck with Skype.)

I understand, but every two weeks is a little overstated don't you think?
I still have ICQ. Everyone left me there already. I also have Jabber, no friends there.
Skype I had for a short time, when Mickeysoft migrated it from MickeySoft Network. And it did not play well on the Linux platform.
Now I have both, WA and TG. And I'm in the opportunity to have my most important friends using TG. Both WA and TG eat a lot of memory. I would be thrilled to shut up one of the two. At least during work hours. A native 3rd party client would settle the argument.

Sailorgram by Dax
https://openrepos.net/content/dax/sailorgram

That is sad news - I still regard Mitakuuluu as one of the better messenger apps out there and you definitely had some eye for privacy as well by adding an app-specific address book (a killer feature for me). So I would like to thank you for the work you have done in the past!

I'm with you with regard to the usage of Telegram - however, most of my friends unfortunately aren't. Well, they'll have to be patient, as I'm now using WhatsUp via Pidgin on my PCs - so no more "instant" messenger. I tell everyone: "If it's urgent, use SMS or Telegram."

Banning users? Switching to a protocol that uses end-to-end encryption by default which happens to break 3rd party clients is not the same as banning users.

I've long been a critic of WhatsApp, I have avoided using it and this has been quite an inconvenience to me. Practically everyone I know uses it and I've missed out on a lot communication as a result. At the same, over the years I've reluctantly had to use other proprietary communication systems to stay in contact with others. WhatsApp just happened to be the latest proprietary new kid on the block, it had many shortcomings, to which I thought "enough is enough," and I chose not to embrace it.

I actually have congratulate WhatsApp on this change. It's come a long way since inception. End-to-end encryption as default puts it above most other proprietary communications in my book, even above SMS.

Of course, WhatsApp is still not perfect. In terms of client support, it still lags behind Telegram whose API and client are fully open. Telegram however, is not an option for me, it is not secure by default and I don't know anyone that uses it. WhatsApp's centralised server means that your address book is probably shared with Facebook who own it. I guess it's a trade-off about what I am willing accept but it looks like they are heading in the right direction and I think I might be ready start using it. All we now is for the Signal protocol to be RE'd implemented so we can have it on our devices.

EDIT: Even better... I just found out that the Signal protocol is open!

Thanks for your effort. Still, would you consider publishing the source code under reasonable open source license so that others may try their luck?

Best regards,
Gert

You have decided wisely!

Why develop a third party client for a closed messenger, which doesn't accept users of a third party app of a system which they are not willing to support.

Maybe the users of such a messenger should think about moving on...