SAN FRANCISCO – For a long time, clicking a link to an X post from another app on Android was an exercise in frustration. The X app would open, spin briefly, and then fail. The post the user came to see simply would not load. It was not a minor glitch. It was a fundamental symptom of a codebase that had accumulated years of technical debt, stretched far beyond what it could reliably sustain.
X launched a rebuilt Android app on Sunday, replacing that creaking foundation with one written entirely in Kotlin and Jetpack Compose. Nikita Bier, the company’s head of product, called it “one of the largest engineering projects” in X’s history. The app, which the company spent nearly a year rebuilding from scratch, is now live on the Google Play Store.
The old Android app was not incrementally improved. It was abandoned. Engineers began the complete rewrite in August 2025 after determining that patching the existing architecture was not workable. The new codebase starts fresh, adopting the same Kotlin-first development stack that Android developers have standardized on since Google declared it the preferred language for Android development. Jetpack Compose handles the interface rendering, a move that promises smoother scrolling, faster load times, and more responsive animations throughout the app.
The difference is immediately apparent to users who remember the previous version. Scrolling through the timeline on the rebuilt app is noticeably faster. Notifications arrive promptly. And critically, posts linked from external apps now load correctly, solving the broken-link problem that plagued the old version. As TechCrunch reported, the previous app’s failure to open linked posts was severe enough to constitute a basic functional failure on Android.
That global dimension matters. Unlike in the United States, where iOS holds a comfortable majority of smartphone usage, Android dominates across South Asia, Southeast Asia, Latin America, and Africa. For X to be a genuinely global platform, its Android experience cannot be an afterthought. Nikita Bier, who earlier this year led the rollout of the React with Video feature for X creators, has described the rebuild as historically significant for the company.
Bier’s characterization of this as a historic engineering undertaking is not obviously wrong. A year-long, ground-up rebuild of a social media app used by hundreds of millions of people is a substantial technical commitment. What makes it more noteworthy is that it was done alongside major headcount reductions and a sustained identity pivot from Twitter to X.
The rebuilt app does not yet do everything the old one could. Several features are still being ported to the new architecture. Spaces, the audio conversation feature, is currently missing. The in-app video editor, which allowed users to trim and adjust clips before posting, is absent. Custom timelines have not yet been ported. React-with-video, the creator engagement format announced earlier this year, is also not available in the rebuilt version at launch.
X has not published a timeline for when these features will return. That absence matters for users who relied on them. Spaces in particular has a dedicated user base; its temporary removal from Android is not a cosmetic gap.
The company claims performance improvements in scrolling and rendering, but independent benchmarks have not been published. X’s own characterization of the rebuild as faster and smoother “in every way” is a marketing claim, not a verified measurement. The proof will come from the experience of users across the full range of Android devices that X needs to serve, including older and mid-range handsets common across its largest global markets.
The deeper question is whether the rebuild addresses structural problems or only surface symptoms. A fresh codebase in modern tooling does not automatically guarantee reliability if the underlying data pipeline, content delivery infrastructure, or recommendation algorithm layers above it remain unchanged. Kotlin and Jetpack Compose improve the developer experience and generally improve rendering efficiency, but they do not fix server-side issues.
For now, the rebuilt app is available through the standard update process. Users on Android should receive it automatically through the Google Play Store. The reception has been cautiously positive, with missing features remaining a real caveat. Whether the new architecture proves durable under the traffic spikes that come with breaking news or live events will take longer to determine.
The company has indicated that optimization for older devices is still in progress. That is the right thing to say. It is also the right thing to actually deliver on, given how much of X’s global Android audience uses mid-range hardware, and how much depends on this rebuild actually being what it claims to be.
