Onegram

Onegram is an unofficial Telegram client for legacy iOS devices.

The project brings modern Telegram functionality to devices and iOS versions that are no longer supported by the official Telegram client, with a particular focus on keeping old hardware usable instead of simply dropping unsupported APIs and features.

Onegram supports iOS 4.3–10 and includes a full compatibility layer for running a large part of the modern client functionality even on an iPhone 4 with iOS 4.3.

Onegram

Version 1.0 is the largest Onegram update so far.

A major part of the client has been reworked for iOS 4 compatibility, including Objective-C++, ARC, C++, libstdc++, GCD, UIKit, CoreImage, MapKit, GLKit, libtgvoip and WebRTC.

Around 85% of the main Onegram functionality is currently implemented and working on iOS 4.3.

Highlights

Full iOS 4.3 port iOS 4.3–10 support Telegram channels Channel post comments Forums and topics Chat folders Voice calls WebRTC calling engine on iOS 4 Voice message / video message switching Modern message history Large chat and channel history pagination Media and image loading Video handling on iOS 4 Channel notification controls Legacy iOS UI compatibility Classic iOS 6 interface Optimizations for 512 MB devices

iOS 4

Onegram does not simply raise the minimum deployment target or disable functionality that does not work on iOS 4.

A large part of the application has been ported to work with the runtime and frameworks available on iOS 4.3.

This includes:

ARC support through ARCLite Objective-C runtime compatibility Objective-C++ compatibility C++ code running through the old libstdc++ runtime libtgvoip compatibility with libstdc++ TgVoipWebrtc port for iOS 4.3 WebRTC DSP compatibility with the old C++ runtime Legacy GCD / libdispatch support UIKit compatibility CoreImage fallbacks Operation without GLKit where it is unavailable MapKit compatibility Replacements for APIs and symbols introduced in iOS 5+

The main C++ part of Onegram and its calling engine can now be built with a real iOS 4.3 deployment target without increasing the minimum version to iOS 5.

Performance

Onegram 1.0 contains major database and performance improvements, especially for older devices.

Some database operations that previously took approximately:

1.5–1.7 seconds

now take approximately:

0.37–0.39 seconds

Other improvements include:

Reduced unnecessary database access Batch processing for several expensive database operations Fewer unnecessary network requests while loading chats Reduced CPU usage while loading the chat list Faster chat-folder switching Reduced unnecessary message-list reloads Optimized user and contact loading Lower application startup load Improved asynchronous media loading

512 MB Devices

Special attention has been given to devices such as the iPhone 4 and iPhone 4S.

Onegram includes:

Memory usage improvements Reduced CPU load Improved chat scrolling stability Fewer crashes while rapidly switching chats Improved asynchronous media loading Optimized database access More stable loading of large chats and channels

Current Status

Onegram is now usable as a regular Telegram client, although some crashes and unfinished functionality may still exist.

The iOS 4 port is approximately 85% complete.

Video messages / video circles are currently one of the main remaining limitations on iOS 4.

Development is ongoing, with additional work focused on stability, compatibility and removing dependencies on APIs and runtime symbols introduced after iOS 4.

Building

The project uses the legacy Telegram iOS architecture and contains Objective-C, Objective-C++, C and C++ code.

Reference development environment:

macOS Mavericks Xcode 4.6.3 iPhoneOS SDK 6.1 Deployment target: iOS 4.3

1. Clone the repository, including its submodules:

   git clone --recursive https://github.com/IllyaGIF/Onegram.git
   cd Onegram

2. Create a local configuration file:

   cp config.h.example config.h

3. Add your own Telegram API credentials to config.h.

4. Open Telegram.xcworkspace in Xcode.

5. Select the Telegraph scheme and configure your bundle identifier and signing settings.

6. Build for an iOS device or simulator.

Do not publish config.h, signing certificates, provisioning profiles or other private credentials.

Download

Prebuilt releases are available from the GitHub Releases section.

License

Onegram is distributed under the GNU General Public License v2.0.

Parts of the project are based on the legacy Telegram for iOS codebase and other open-source components included in the repository.

Disclaimer

Onegram is an unofficial Telegram client and is not affiliated with or endorsed by Telegram.

The project exists to keep Telegram usable on legacy iOS devices that are no longer supported by current official releases.