Welcome back to This Week in Apps, the weekly TechCrunch series that recaps the latest in mobile OS news, mobile applications and the overall app economy.

The app industry continues to grow, with a record number of downloads and consumer spending across both the iOS and Google Play stores combined in 2021, according to the latest year-end reports. App Annie says global spending across iOS and Google Play is up to $135 billion in 2021, and that figure will likely be higher when its annual report, including third-party app stores in China, is released next year. Consumers also downloaded 10 billion more apps this year than in 2020, reaching nearly 140 billion in new installs, it found.

Apps aren’t just a way to pass idle hours — they’re also a big business. In 2019, mobile-first companies had a combined $544 billion valuation, 6.5x higher than those without a mobile focus. In 2020, investors poured $73 billion in capital into mobile companies — a figure that was up 27% year-over-year.

This Week in Apps offers a way to keep up with this fast-moving industry in one place with the latest from the world of apps, including news, updates, startup fundings, mergers and acquisitions, and much more.

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Top Stories

Elon says he's killing the Twitter deal

The bird app buyout could be off, if Elon Musk has his way.

On Friday, Musk's legal team informed Twitter the Tesla and SpaceX exec would be terminating the merger agreement because, as their letter alleges, Twitter made false and misleading claims about the health of its business. This, of course, refers to the drama Musk had been stirring up over the percentage of bots on the service, which Twitter says is estimated to be less than 5%. Upon Musk's earlier pressing for more information on this figure, Twitter provided Musk's team with API access to make their own determinations. The letter, however, states that this API access was capped and limited, preventing the team from being able to accurately analyze Twitter's data with regard to bots. (Which makes Musk's claims that the bot count is higher than Twitter said it was a bit hard to prove!) Musk's lawyers also allege Twitter included known fake and bot accounts in its mDAUs and didn't have a standard process for calculating its mDAUs or the percentage of bots. Even if the arguments were valid -- and that's not able to be determined at this time -- they don't allow Musk to simply walk away.