Yes. You read it right. 3Speak & Hive - both heavily condemn centralised ecosystems like Apple's AppStore & Google PlayStore.

Initially we thought of purchasing Apple's Enterprise distribution license
That is still controlled by Apple.
So, I used my personal account for distributing app via TestFlight for iOS users.
We were actively doing research work on finding alternative to Apple's AppStore & TestFlight.

Video illustrating App install via AltStore

We managed to find a way to distribute apps using alternative.
It doesn't require to go through Apple's review system.
Please refer to attached video above.
In video, I've illustrated how easily users can install the 3Speak - Acela app on their iOS Devices.

AltStore loads data from json file.
JSON file is placed here - https://gitlab.com/sag333ar/sagarkothari88-altstore
Anyone can take a look at that app.json file.
AltStore loads resources specified in that json file.
Resources are placed here - https://github.com/spknetwork/Android-App/releases/tag/v1.0.3_48
AltStore downloads ipa file from Github release
And it installs app directly on user's device.
From Github ipa to iOS device. iPA is NOT touched.
There is no security risk involved in this.

Install 3Speak - Acela App - on your iOS Device with 5 easy steps

Those 5 steps - are only for the first-timers.
Once you're done with following 5 steps, all you'll require to do is hit UPDATE button in future.

Once Installed, connect your iOS device to your system.
Install AltStore on your iOS Device

As a user, We are deciding what to install & from where to install.
Let's add custom source - 3Speak's App's Source.
Open AltStore App & Switch to second tab called "Browse"
Now, tap on "Sources" button on top right corner.
Now, click on that "+" plus button on top-left corner
Now, copy following link & paste it in the input box shown below.
https://gitlab.com/sag333ar/sagarkothari88-altstore/-/raw/main/app.json?inline=false
You're all set. This is one time in life-time set up.
Once you do this, you'll always get updates from 3Speak App.
Added source should show up as follows.

Open AltStore App & Switch to "Browse" (second) tab.
Scroll down.
Tap on Free button & install app.
Now, tap on "Open" button to launch app.
Make sure your iOS Device is connected to your system & AltServer is running on your system.

Download AltStore iPA using following link (which allows custom JSON)
https://github.com/spknetwork/Android-App/releases/download/v1.0.3_48/altStore_app_which_allows_custom_sources.ipa
Now copy that iPA file to your iPhone
e.g. I've used VLC's file-share-feature to copy it to my iPhone.