Pros of Telegram

• Open-source Android client, allowing for community contributions and audits
• More frequent updates and commits, potentially leading to faster feature implementation
• Larger community of contributors, which may result in diverse perspectives and improvements

Cons of Telegram

• Less official support compared to the iOS version, as it's not maintained by Telegram directly
• Potential for inconsistencies with the official iOS app in terms of features and design
• May have more bugs or stability issues due to community-driven development

Code Comparison

Telegram (Android):

public class MessageObject {
    public TLRPC.Message messageOwner;
    public CharSequence messageText;
    public int type;
    public int messageId;
    // ... more properties and methods
}

Telegram-iOS:

public final class Message: Equatable {
    public let id: Int32
    public let flags: Int32
    public let peerId: PeerId
    public let timestamp: Int32
    // ... more properties and methods
}

The Android version uses a more Java-centric approach with a single class containing various properties, while the iOS version follows Swift conventions with a more structured and type-safe implementation.

Pros of TelegramSwift

• Written in Swift, providing better performance and safety features
• More modern codebase, potentially easier to maintain and extend
• Smaller repository size, possibly indicating a more focused and efficient implementation

Cons of TelegramSwift

• Less official support and updates compared to the official Telegram-iOS repository
• Potentially missing some features or optimizations present in the official app
• May have compatibility issues with future Telegram API changes

Code Comparison

TelegramSwift:

func presentationData(theme: PresentationTheme? = nil, strings: PresentationStrings? = nil, dateTimeFormat: PresentationDateTimeFormat? = nil, nameDisplayOrder: PresentationPersonNameOrder? = nil, disableAnimations: Bool? = nil, largeEmoji: Bool? = nil, chatMode: PresentationChatMode? = nil) -> PresentationData {
    // Implementation
}

Telegram-iOS:

- (void)updateThemeAndStrings {
    [self updateTheme:[self generateTheme]];
    [self updateStrings:[self generatePresentationStrings]];
    [self updateDateTimeFormat:[self generateDateTimeFormat]];
    // Additional implementation
}

The code comparison shows that TelegramSwift uses Swift's more modern syntax and type system, while Telegram-iOS uses Objective-C. This difference in language choice affects the overall structure and readability of the codebase.

Pros of Telegram-iOS

• Open-source nature allows for community contributions and transparency
• Regularly updated with new features and security improvements
• Comprehensive documentation for developers

Cons of Telegram-iOS

• Large codebase may be challenging for new contributors to navigate
• Requires significant resources to build and run locally
• Some features may be platform-specific and not available on all iOS devices

Code Comparison

Both repositories contain the same codebase, as they are the same project. Here's a sample of the Swift code used in the Telegram-iOS app:

import Foundation
import SwiftSignalKit
import Postbox

public final class TelegramEngine {
    public let account: Account
    
    public init(account: Account) {
        self.account = account
    }
}

This code snippet demonstrates the initialization of the TelegramEngine class, which is a core component of the Telegram-iOS app. It imports necessary modules and sets up the account property.

Since both repositories are identical, there are no differences in the codebase to compare. The Telegram-iOS project is a single, unified repository for the iOS version of the Telegram messaging app.

Pros of tg

• Written in C, potentially offering better performance and lower resource usage
• Command-line interface allows for more flexibility and scripting capabilities
• Supports multiple accounts and session management

Cons of tg

• Less user-friendly for non-technical users compared to the official iOS app
• Limited graphical interface and multimedia features
• May lack some of the latest Telegram features and updates

Code Comparison

tg (CLI-based approach):

void send_message (peer_id_t id, const char *text) {
  clear_packet ();
  out_int (CODE_messages_send_message);
  out_peer_id (id);
  out_string (text);
  out_long (0);
  send_packet ();
}

Telegram-iOS (UI-driven approach):

func sendMessage(text: String, to peerId: PeerId) {
    let message = EnqueueMessage.message(text: text, attributes: [])
    let _ = enqueueMessages(account: self.account, peerId: peerId, messages: [message])
}

The tg repository uses a lower-level C implementation for sending messages, while Telegram-iOS employs Swift with higher-level abstractions and integration with the iOS UI framework.

Pros of td

• Cross-platform library, supporting multiple programming languages
• More flexible and customizable for developers building Telegram clients
• Provides lower-level access to Telegram API functionality

Cons of td

• Requires more development effort to create a full-featured client
• Less user-friendly for non-developers or those seeking a ready-to-use solution
• May have a steeper learning curve compared to Telegram-iOS

Code Comparison

td (C++):

auto send_message = td_api::make_object<td_api::sendMessage>();
send_message->chat_id_ = chat_id;
send_message->input_message_content_ = td_api::make_object<td_api::inputMessageText>();
send_message->input_message_content_->as_input_message_text()->text_ = td_api::make_object<td_api::formattedText>();
send_message->input_message_content_->as_input_message_text()->text_->text_ = "Hello, World!";
send_query(std::move(send_message), {});

Telegram-iOS (Swift):

let params = SendMessageParams(chatId: chatId, text: "Hello, World!")
let signal = context.engine.messages.sendMessage(params)
signal.start(next: { result in
    print("Message sent successfully")
})

The td library provides more granular control over message composition and sending, while Telegram-iOS offers a more abstracted and simplified approach tailored for iOS development. td's flexibility comes at the cost of increased complexity, whereas Telegram-iOS provides a more streamlined experience for iOS-specific development.