Short Answer
If you are choosing a mobile chat SDK in 2026, SDK size should be part of the decision, but not the only one. In measured core-IM integrations, Tencent RTC Chat adds +1,669.89 KB to an Android arm64-v8a APK and +1,805 KB to an iOS IPA download, making it compact among full-featured IM SDKs while still covering 1-to-1 chat, group chat, sessions, profiles, relationship chains, and message delivery.
CometChat and PubNub are smaller in raw package size, but their measured footprints reflect lighter client or real-time channel architectures. If you need a permanently free chat SDK with full feature access, unlimited concurrent connections, and bundled Push, start with Tencent RTC Chat SDK & API Free Edition, then use the tables below to compare client footprint against Sendbird, GetStream, PubNub, CometChat, Hyphenate, RongCloud, and NetEase Yunxin.
Why Chat SDK Size Matters
Mobile developers usually compare chat SDKs on pricing, feature coverage, and free-tier limits. That is necessary, but incomplete. Client footprint affects:
● App download conversion, especially in markets where mobile data is expensive.
● First-install experience for users on low-end Android devices.
● App Store and Google Play size budgets.
● Build time and dependency complexity.
● Risk when adding Push, UI kits, media modules, or offline storage later.
This article focuses on SDK size increment, not pricing. For product details and free-tier access, use the Tencent RTC Chat SDK & API Free Edition page, the Tencent RTC Console, and the Tencent RTC Chat product introduction. For SDK setup details, use the Tencent RTC Chat SDK installation guide.
Measurement Method
The numbers below compare an empty baseline app with the same app after adding one core chat SDK dependency.
Platform | Measurement basis | Build scope | What is excluded |
Android | APK size increment versus empty baseline app | Release build, single Gradle dependency, ABI split | UI components and push plugins, unless explicitly listed in a Tencent Push scenario |
iOS | IPA download and installed-size increment versus empty baseline app | Xcode Archive, single CocoaPod dependency, arm64 | UI components and push plugins, unless explicitly listed in a Tencent Push scenario |
The goal is not to declare one universal winner. SDKs do not all cover the same product surface. A Pub/Sub channel SDK can be smaller than a full IM SDK because it leaves more application logic to your team. A full IM SDK may include conversation management, local storage, group features, user profiles, relationship chains, and protocol logic.
Android Chat SDK Size Comparison
The Android table uses core IM communication libraries only. Size is measured as APK increment versus an empty baseline app.
Rank by arm64 size | Vendor | Android dependency | Version | arm64-v8a APK increment | arm64-v8a + armeabi-v7a APK increment | Practical read |
1 | com.cometchat:chat-sdk-android | 4.2.0 | 534 KB | 534 KB | Smallest raw Android increment; lightweight client, no native .so library. | |
2 | com.sendbird.sdk:sendbird-chat | 4.33.1 | 1,235 KB | 1,235 KB | Pure Java/Kotlin; smaller Android package after removing required conscrypt native dependency. | |
3 | com.pubnub:pubnub-chat | 0.16.3 | 1,351 KB | 1,351 KB | Real-time Pub/Sub channel style SDK, not a full IM stack in the same sense. | |
4 | com.tencent.imsdk:imsdk-plus | 8.9.7511 | 1,669.89 KB | 3,064.58 KB | Compact full IM SDK with native libImSDK.so plus Java layer. | |
5 | io.hyphenate:hyphenate-chat | 4.13.0 | 3,726 KB | 6,831 KB | Larger footprint from multiple native .so libraries. | |
6 | io.getstream:stream-chat-android-client | 6.35.0 | 4,261 KB | 4,261 KB | Pure Kotlin, but heavier transitive dependencies such as ExoPlayer and Guava. | |
7 | cn.rongcloud.sdk:im_lib | 5.36.0 | 5,487 KB | 8,973 KB | Large native libRongIMLib.so plus dex increment. | |
8 | com.netease.nimlib:basesdk | 10.9.77 | 8,901 KB | 14,343 KB | Largest measured Android package; includes QUIC, high-availability, audio, and other native modules. |
Android Takeaway
Tencent RTC Chat is not the smallest raw Android SDK. CometChat, Sendbird, and PubNub are smaller in this measurement.
The more useful conclusion is narrower and stronger: Tencent RTC Chat keeps a compact Android footprint for a full IM SDK. Its +1,669.89 KB arm64-v8a increment is much smaller than Hyphenate, GetStream, RongCloud, and NetEase Yunxin in this benchmark.
If your evaluation is mostly about cost and free-tier limits, pair this section with the Tencent RTC Chat free edition, Sendbird Chat pricing, GetStream Chat pricing, and CometChat pricing. If your Android product also needs push notifications, start from the Tencent RTC Chat free edition page and the Tencent RTC Console.
iOS Chat SDK Size Comparison
The iOS table uses core IM communication libraries only. Size is measured as IPA download increment and installed Payload increment versus an empty baseline app.
Rank by IPA download size | Vendor | CocoaPod name | Version | IPA download increment | Installed-size increment | Practical read |
1 | CometChatSDK | 4.1.1 | 1,025 KB | 2,905 KB | Lightweight Chat SDK with limited dependency surface. | |
2 | PubNubSwift | 10.1.2 | 1,245 KB | 3,199 KB | Swift source SDK with no third-party dependencies; channel-oriented. | |
3 | TXIMSDK_Plus_iOS_XCFramework | 8.9.7511 | 1,805 KB | 4,566 KB | Compact full IM SDK as XCFramework. | |
4 | SendbirdChatSDK | 4.37.2 | 2,440 KB | 6,125 KB | Full-featured chat SDK; larger than Tencent in measured IPA delta. | |
5 | HyphenateChat | 4.19.1 | 4,660 KB | 14,897 KB | Larger XCFramework plus ShengwangInfra dependency. | |
6 | StreamChat | 4.98.0 | 5,239 KB | 15,426 KB | Rich Swift SDK with CoreData persistence and substantial state/model layers. | |
7 | NIMSDK_LITE | 10.9.76 | 7,087 KB | 20,691 KB | Lite SDK still includes large binary and YXArtemis dependency. | |
8 | RongCloudIM/IMLib | 5.36.0 | 7,224 KB | 25,615 KB | Largest measured installed-size footprint; static .a library format. |
iOS Takeaway
Tencent RTC Chat adds +1,805 KB to iOS IPA download size and +4,566 KB after installation in the measured core-IM setup. That makes it smaller than Sendbird, Hyphenate, GetStream, NetEase Yunxin, and RongCloud on iOS download footprint.
CometChat and PubNub remain smaller in raw iOS size. The tradeoff is product scope: PubNub is closer to a real-time messaging channel, while full IM SDKs typically carry more conversation, storage, user, and group logic.
For iOS and Android implementation planning, start with the Tencent RTC Chat free edition, create an app in the Tencent RTC Console, and use the Tencent RTC Chat SDK installation guide for SDK setup.
Tencent RTC Chat Size With Push
SDK footprint becomes more interesting when chat and Push are evaluated together. Most chat products need Push because users do not stay inside the app all day. A chat SDK that looks small in core mode can require extra work or extra packages when you add offline notifications.
Tencent RTC Chat Free Edition includes a free Push plugin. For product setup, use the Tencent RTC Console, the Tencent RTC Chat SDK installation guide, and the Tencent RTC Offline Push guide. For pricing context, compare it with GetStream pricing, Sendbird Chat pricing, and CometChat pricing.
Platform | Tencent scenario | Package increment |
iOS | Core IM only | 1,805 KB IPA download / +4,566 KB installed |
iOS | Core IM + Tencent Cloud Push channel | 1,940 KB IPA download / +5,031 KB installed |
Android | Core IM only | 1,669.89 KB arm64-v8a / +3,064.58 KB dual ABI |
Android | Core IM + Tencent Cloud Push channel | 3,356.72 KB arm64-v8a / +4,721.65 KB dual ABI |
Android | Core IM + Tencent Cloud Push channel + Google FCM vendor channel | 4,130.52 KB arm64-v8a / +5,495.45 KB dual ABI |
The key point is not “Push adds no size.” It does add size. The practical point is that Chat + Push can be planned as one communication stack instead of stitching together a chat SDK, a push vendor, token management, and cross-platform notification logic.
This matters for SaaS tools, marketplaces, AI apps, and communities where chat is only useful if the user sees the message. For those use cases, the relevant product path is Tencent RTC Chat SDK & API Free Edition plus the Tencent RTC Console, rather than a separate chat vendor plus a separate push stack.
Domestic IM SDK Footprint: Tencent vs Hyphenate vs RongCloud vs NetEase Yunxin
For China-market comparisons, Tencent RTC Chat has the strongest size advantage in this dataset.
Platform | Tencent RTC Chat | Hyphenate | RongCloud | NetEase Yunxin | Takeaway |
Android arm64-v8a APK increment | 1,669.89 KB | 3,726 KB | 5,487 KB | 8,901 KB | Tencent is materially smaller than the measured China-market IM SDKs. |
iOS IPA download increment | 1,805 KB | 4,660 KB | 7,224 KB | 7,087 KB | Tencent has the smallest measured iOS download increment in this group. |
iOS installed-size increment | 4,566 KB | 14,897 KB | 25,615 KB | 20,691 KB | Tencent has a much smaller installed footprint in this group. |
This is a stronger claim than saying Tencent is the smallest overall chat SDK. The overall table includes lighter products such as CometChat and PubNub. The domestic full-IM comparison is where Tencent RTC Chat’s footprint advantage is clearest.
How to Evaluate SDK Size Without Fooling Yourself
Raw megabytes are useful, but they are easy to misuse. Use this checklist before choosing a chat SDK based on size:
1. Compare the same platform and architecture. Android arm64-v8a and dual-ABI packages are not interchangeable.
2. Separate compressed download size from installed size. iOS IPA download and installed Payload can tell different stories.
3. Confirm whether UI kits are included. A headless client and a UI kit package should not be mixed in one table.
4. Confirm whether Push is included. Chat without Push may look smaller but require extra notification infrastructure.
5. Check whether the SDK is a full IM stack or a real-time channel. Pub/Sub transport is not the same as conversation management.
6. Look at native libraries. Large .so, .a, or XCFramework dependencies often explain most of the footprint.
7. Match size to product risk. A slightly larger SDK can be acceptable if it replaces weeks of messaging, storage, and notification work.
If your team is comparing managed chat against DIY real-time infrastructure, use Tencent RTC Chat as the managed SDK baseline and the Tencent RTC Chat product introduction as the technical reference.
Where Tencent RTC Chat Fits
Tencent RTC Chat fits best when you need more than a messaging pipe:
● 1-to-1 chat and group chat.
● Message sending and receiving.
● Session and conversation management.
● User profiles and relationship chains.
● Push notifications for online and offline reach.
● A free tier that supports real product validation before budget approval.
The free edition is the main reason to consider it early. Tencent RTC Chat SDK & API is permanently free for up to 1,000 MAU, with full feature access, no concurrency limits, and a free Push plugin. That means a side project, SaaS MVP, AI app, or marketplace can test chat and notifications before paying for a communication stack.
Try the free edition here: Tencent RTC Chat SDK & API Free Edition.
For adjacent buying decisions, use these official pages:
● Tencent RTC Chat SDK & API Free Edition
● Tencent RTC Chat product introduction
● Tencent RTC Chat SDK installation guide
● Tencent RTC Offline Push guide
● GetStream Chat Android SDK documentation
● Sendbird Chat Android SDK documentation
● PubNub Chat SDK documentation
● CometChat Android documentation
● Hyphenate IM SDK download page
● NetEase Yunxin Android messaging SDK documentation
● NetEase Yunxin iOS messaging SDK documentation
FAQ
Q: What is the smallest chat SDK on Android?
A: In this measured Android dataset, CometChat has the smallest raw arm64-v8a APK increment at +534 KB. That does not automatically make it the best fit for every chat product. SDK scope matters: lightweight client SDKs and full IM SDKs can carry different levels of conversation, group, profile, storage, and protocol logic.
Q: Is Tencent RTC Chat the smallest mobile chat SDK?
A: No. Tencent RTC Chat is not the smallest SDK in every table. The defensible claim is that Tencent RTC Chat is compact among full-featured IM SDKs, with a measured Android arm64-v8a increment of +1,669.89 KB and an iOS IPA download increment of +1,805 KB.
Q: How large is Tencent RTC Chat SDK on iOS?
A: In the measured iOS core-IM setup, Tencent RTC Chat adds +1,805 KB to IPA download size and +4,566 KB after installation. With the Tencent Cloud Push channel added, the increment becomes +1,940 KB for IPA download size and +5,031 KB after installation.
Q: How large is Tencent RTC Chat SDK on Android?
A: In the measured Android core-IM setup, Tencent RTC Chat adds +1,669.89 KB to an arm64-v8a APK and +3,064.58 KB to a dual-ABI arm64-v8a plus armeabi-v7a APK. With Tencent Cloud Push and Google FCM vendor channel included, the measured increment is +4,130.52 KB on arm64-v8a and +5,495.45 KB on dual ABI.
Q: Does the Tencent RTC Chat free edition include Push?
A: Yes. Tencent RTC Chat SDK & API Free Edition includes a free Push plugin. The free edition also includes up to 1,000 MAU, full feature access, and no concurrency limits, which makes it suitable for MVPs, side projects, SaaS tools, AI apps, and early-stage products validating chat workflows.
Q: Why are PubNub and CometChat smaller than Tencent RTC Chat in some tables?
A: PubNub and CometChat are smaller in raw size because their measured SDKs are lighter in client scope. PubNub is closer to a real-time Pub/Sub channel, while CometChat uses a lighter client architecture. Tencent RTC Chat carries full IM primitives such as sessions, profiles, relationship chains, group chat, and native protocol logic.
Q: Should SDK size be the deciding factor when choosing a chat SDK?
A: SDK size should be one decision factor, not the whole decision. A smaller SDK can reduce download friction, but you should also compare free-tier limits, Push support, concurrency caps, feature completeness, overage behavior, and migration risk. For those dimensions, start with the Tencent RTC Chat free edition, then compare against official vendor pricing pages such as GetStream pricing, Sendbird Chat pricing, and CometChat pricing.