Every year for the past five, we have run our regular reviews of some long established and some newly arrived privacy claiming messenger service providers. A series we have cheekily subtitled as "Secure or not too secure?" to paraphase the great communicator, William Shakespeare :-)
During the course of last year, we conducted another 9 reviews and these are attached below. We haven't done it as a 'ranked' exercise, we have our favourites but are just laying out our findings for you to see and use to maybe find the service for you but with eyes, hopefully, slightly wider open!
Since iOS 14.3 Apple introduced their privacy 'invasion' screens to all apps, we believe it is worth extending that to all the reveiwed services so we've attached these with some comments.
February - The 2020 Review Series Kickoff

March - Telegram

Telegram uses a few identifiers that are directly linked to you. They also have your contacts synced and stored in plain text format! Remember you do not need to give permission for some of these. Telegram does, however, let you disable the upload of your telephone book. On Android install the FOSS version from F-Droid but again do not give permission to upload your contacts.
April - Threema


Threema asks you if you would like to sync your contacts and, if so, they are encrypted on their server. The Identifier is a Threema ID, not your telephone number or email address, unless you select either of these. If you are an Android user, do not use the Google version, but get Threema over the APK on the website, also use polling which switches off any Google involvements.
May - Wire


Usage data? What? And why?
June - Nextcloud Talk

Nextcloud hasn't updated the app since this feature was introduced. So we need to wait for the next submition to the app store to see what they have planned for us. However, remember you host can this one yourself! For the Android users amongst us without Google Play we still don't get notifications of incoming messages! Sad!
July - Status


Way to go! Push notifications have also been fixed since our review. APK is provided on the website for all Android users.
August - Delta Chat

No update since 14.3 was introduced, so we need to wait for the next one to see this. For Android users Delta Chat is available via F-Droid, get it there!
September - XMPP/Conversations
An Android app, self-hosted solutions are always the best!
October - SchildiChat

They've got a desktop version now as well, for Android, my favorite matrix app!
November - Element


As mentioned, the King of Metadata! Yet you can self-host it which puts a lot of the control back into your own hands.
December - Signal


As you can see, Signal really does well when it comes to metadata!
Messenger
Even though not reviewed by us, here's a look at how Facebook Messenger scores!

The Privacy Advocate's final few words...
We've had our say on each of the messenger service providers shown for 2020 (and you can find others from the past in the Messengers tag archive) and we'll continue looking to re-review the same messengers and additional new ones in 2021.
It's not for us to dictate whether you stick with WhatsApp or Facebook Messenger but we know who and what they are so won't even bother reviewing them. But you could just ask yourself one simple question: is it worth it or right to have your metadata collected and in some cases sold to third parties? Is it worth seeing governments and law enforcement arresting people as they're demonstrating for their rights?
At the same time, what is important for you? Telegram has great channels for news and announcements and the secret chats are probably good enough for most people. If you want someone in the bar or that you've just meet to give you a contact and they offer their WhatsApp account, it's probably not appropriate explaining how Element works better, being as its decentralized, at the end of the day (night) you just want the contact ;) But you could suggest quickly downloading Signal, it only takes a few seconds and then they'll be ready to text you securely.
If you are an iOS user, and the other end is on iMessage, well, for the quick contact? Well ok but don't forget to sign out of the iCloud. Apple claims if you don't sync with the iCloud the encryption key stays on the device. This is, of course, in an Apple closed-source garden (although even I have to admit, Apple does now publish some white papers and code). However, as mentioned, all are better than WhatsApp and Messenger.
Threema is mostly open-source now, and is another great messenger, but it costs money, so it's not easy to give someone that option when you've just met them.
Ultimately, it's all about your personal threat level, or even how comfortable you are potentially sharing your metadata. Every step counts, every improvement is a step forward and each of the messengers reviewed will definitely be an upgrade to what most people are using e.g. WhatsApp and Messenger!
I use Element as my first choice with like-minded people, but I also use Threema and Signal. The latter because it is the easiest way to convince someone to switch. If the person is not willing to download an app, which is ready within seconds, you maybe want to re-evaluate the relationship!!!
Stay safe and expect many new messenger reviews here in decentralize.today over 2021.
Reference Link - The 2019 review of Messenger Service Providers: Results
