Today in Tech: Big Yahoo layoffs today, Instagram hits Android by JP Mangalindan @FortuneMagazine April 4, 2012, 7:40 AM EST E-mail Tweet Facebook Google Plus Linkedin Share icons Fortune’s curated selection of tech stories from the last 24 hours. Sign up to get the round-up delivered to you each and every day. * Facebook countered Yahoo’s YHOO lawsuit with a lawsuit of its own, spanning 10 patents covering areas like homepage, photos, and ads. (Friending Facebook Blog) * Instagram, the popular photo-sharing app with over 30 million users, just officially arrived on Google’s Android operating system. (TechCrunch) * Up to 2,000 Yahoo employees could be laid off later today in nearly every unit, with the products division expected to be the worst hit. (All Things D) * Amazon AMZN is reportedly testing a service that will let Kindle Fire users buy items and subscriptions via mobile apps. In return, the company will take a 30% commission. Such a move would help Amazon remain competitive with Apple AAPL and Google GOOG , which already have similar services in place. (Bloomberg) * How Apple could become the first $1 trillion company. (Fortune) * Meet the iBrain, a small device that could allow people like physicist Stephen Hawking to communicate simply by thinking. (The New York Times) Don’t miss the latest tech news. Sign up now to get Today in Tech emailed every morning.