Iron Messenger
A fast messenger app for Android is one that has less to load before it draws your chats. Iron Messenger 3.12.0 is built that way: since 31 October 2026 its Android app is written natively in Kotlin, with no JavaScript engine inside, and the download is about 4–5 MB. This post gives the measurements, explains why a native app starts faster, and tells how Iron Messenger Lite grew into the main Android app.
How fast is the Iron Messenger Android app?
We measure on two phones that sit on our desk. These are the numbers:
| Huawei (Kirin 710F, Android 10) | Xiaomi Mi Note 2 (Snapdragon 821, Android 8) | |
|---|---|---|
| Open the app to the chat list | 0.47 s | 0.71 s |
| Open a chat | 0.22 s | 0.21 s |
| Frames that miss the screen's refresh while you scroll | 2.0 % | 1.8 % |
They are from 25 October 2026, with the release build, and each is the middle value of several runs. We took them on Iron Messenger Lite, the app that the new main app was built from, before the main app's own extras were added on top. So read them as what this design does on two modest phones. A slower phone will be slower.
The chat list appears from a copy stored on the phone, so it does not wait for the network, and then it updates. Our budgets are 800 ms for the start and 250 ms for opening a chat, and both phones are inside them.
Why does a native app start faster?
When you open an app, the phone has to load it before it can draw anything. A React Native app loads two things: Android's own code, and a JavaScript engine that then reads the app's code and runs it. A native app loads only Android's code, and most of that code is already compiled for your phone.
That has three effects you can see:
- Start time. There is less to load before the first screen, so the first screen comes sooner.
- Download size. The engine and its libraries were most of the old 42 MB. The native Iron Messenger app is about 4–5 MB.
- Which phones can install it. The React Native app needed Android 7 and a 64-bit phone. The native app has no native libraries, so it is not tied to one kind of chip. It still needs Android 7 or newer, and it installs on 32-bit phones.
The React Native code is not slow by itself, and it keeps its place: it is the web version and the Windows app, where there is no other choice. But on Android a second engine always costs a start-up, and a native app does not pay it.
A messenger that opens before you finish blinking. Free, no phone number needed, the same account in every app.
What is a Baseline Profile, and what did it change?
Android does not turn an app into fast machine code the moment you install it. It starts with slower code and compiles the hot parts later, while the phone is idle. Until that happens, the app starts slower than it will later.
A Baseline Profile fixes that. It is a list, shipped inside the app, of the classes and functions that start-up always uses. Android reads it at install and compiles exactly those parts ahead of time. Nothing changes on the screen, and the app simply starts from compiled code.
The numbers on the same two phones, with and without the profile:
- Xiaomi Mi Note 2: from 919 ms to 705 ms, which is 23 % faster.
- Huawei: from 515 ms to 470 ms, which is 9 % faster.
The older, slower phone gains more, because it has more to save. A sideloaded install gets the profile at the first launch, and Android compiles with it at its next idle time, so the very first run after an install can still be slower.
Why did Lite become the main Android app?
Speed is the reason people keep a messenger. You open it dozens of times a day, and every time you meet the same thing first: how long the chat list takes. We built Iron Messenger Lite to answer that on phones where the main app was slow. An earlier post tells that part.
Then Lite kept growing. It got groups, channels, comments, polls, stickers, GIFs, videos, link cards and Instant View, themes and notifications, until it did nearly all of what the main app does and opened faster. At that point the question changed. It was no longer "who needs the small version?" but "why should anybody wait for the big one?"
On 31 October 2026 we made the decision and shipped it. Iron Messenger 3.12.0 is a copy of Lite's work under the main app's own name, icon and package, with Premium and the main app's features added on top. Because the package and the signing key are the same, Android installs it as an ordinary update. Our post about the rebuilt Android app covers what that means for you: staying signed in, where to get it and what is missing.
Already have Iron Messenger? Update it. Same app, a fraction of the weight, and a faster start.
What happens to Lite, the web version and Windows?
Iron Messenger Lite stays as its own app, with its own icon, on the same account. It is the smaller one: about 3.5 MB, and it needs Android 6 or newer, one version lower than the main app. You can run it next to the main app, with the same chats and contacts in both. Today Lite is a direct download from our website. It sells nothing, so there is no in-app purchase in it, and Premium is bought in the main app.
The web version and the Windows app did not change. They are still the React Native code, and they keep working as before. There is no iOS app.
Messages are protected in transit with HTTPS and stored on our server, as before. A rebuild does not change that, and Iron Messenger is not end-to-end encrypted. What Iron Messenger is covers the whole messenger, and the home page has every download.
Questions people ask
How fast does the Iron Messenger Android app open?
On our two test phones, Iron Messenger opens the chat list in 0.47 and 0.71 seconds and a chat in about 0.22 seconds. We measured this on 25 October 2026 with the release build of Iron Messenger Lite, the app the new main app was built from.
Why is a native Android app faster than React Native?
A React Native app loads a JavaScript engine on top of Android's own code, and a native Kotlin app does not. Iron Messenger therefore has less to load before it draws the chat list, and it downloads at about 4–5 MB instead of about 42 MB.
What is a Baseline Profile in Android?
A Baseline Profile is a list inside the app of the code that start-up uses, so Android compiles it ahead of time at install. In Iron Messenger Lite it made the start 23 % faster on a Xiaomi Mi Note 2 and 9 % faster on a Huawei.
Did Iron Messenger Lite replace the main Iron Messenger app?
Iron Messenger 3.12.0 for Android is built from Iron Messenger Lite, under the main app's name and package, so it installs as an update. Iron Messenger Lite stays as its own smaller app, and the web version and Windows app did not change.
