T-Mobile, Metro PCS: T-Mobile and MetroPCS announced Thursday that they have cleared the last regulatory hurdle to their merger, which now requires only the approval of MetroPCS shareholders.

The companies received blessings for the merger from the Federal Communications Commission and the Department of Justice earlier this month and announced Thursday that the move had also received clearance from the Committee on Foreign Investment in the United States. The committee had to review the proposed deal because T-Mobile’s parent company, Deustche Telekom, is based in Germany.

A shareholder vote on the proposed merger has been scheduled for April 12, the companies said in their release.

Medical apps: An official from the Food and Drug Administration said in a Thursday hearing before the House subpanel on oversight and investigation that the agency will release final guidance on its regulation of mobile apps by the end of the fiscal year.

Christy Foreman, director of the FDA’s office of device evaluation, testified that the agency intends to closely regulate only a small subset of apps — namely those that act with or replicate the functions of devices already regulated by the FDA.

As to the question of whether apps would be subject to medical device taxes under the Affordable Care Act, Foreman largely referred lawmakers to the Internal Revenue Service for guidance. She did, however, say she believes medical apps will either not qualify to be taxed or will be exempt from such taxes.

Location tracking bill: Rep. Jason Chaffetz (R-Utah) introduced a bill in the Senate on Thursday, titled the Geolocation Privacy and Surveillance Act, that would require law enforcement officials to obtain warrants based on probable cause before tracking someone using GPS or cellphone location data.

Sen. Ron Wyden (D-Ore.), who backed a previous version of the bill with Chaffetz last year, will introduce companion legislation in the Senate.

The bills were hailed by privacy advocates such as the American Civil Liberties Union’s legislative counsel Chris Calabrese, who said that they would define the “appropriate checks and balances” between law enforcement needs and privacy concerns.

“Innocent people shouldn’t have to sacrifice their privacy in order to have a cell phone,” he said in an e-mailed statement.

Twitter turns 7: Twitter is celebrating its 7th birthday, releasing a video that documents the company’s growth from concept to global communications platform.

The company said that users send over 400 million tweets per day, taking care to highlight that its network is used to connect celebrities, politicians and other notable figures.

As the company grows, however, it continues to face questions about how best to navigate global laws regarding speech. It reported in January that it had received more than 1,000 requests for information from world governments — mostly, the company said, in connection with criminal investigations.

Apple releases environmental report: Apple released its annual environmental report Friday, highlighting the fact that it has moved 75 percent of its energy consumption for its corporate facilities to clean energy sources. All of its facilities at its home base in Cupertino, Calif., now run on renewable energy, the company said, adding that it will continue to expand its efforts in that area.

For example, Apple product manager Scott Brodrick told The Washington Post, the company has plans to install another solar-voltaic array and fuel cell at its massive North Carolina data center in order to double its on-site energy production as consumer demand for storage continues to grow.