Google is at a crossroads with its mobile efforts. Android is by far the most popular phone platform in the world, having long since overtaken Apple’s iOS. While Google runs Android as an open source project, the mobile industry it is driving is remarkably locked down. For Google to do what it wants to do with Android, something has to change. There is one move Google can make that could totally upend the mobile industry and make Android into the operating system Mountain View always wanted — Google has to buy T-Mobile.

This has been rumored on and off for a few years, but it has never made more sense than it does right now. T-Mobile and Google need each other, and here’s why.

Google sucks at retail

Google has successfully reminded everyone over the last few weeks that it has no retail experience, and it’s a real disaster when it tries to pretend otherwise. It’s admirable that Google is looking to sell a new unlocked device like the Nexus 4 through the Play Store, but the launch may have driven away as many customers as it attracted.

Users that tried to buy the device were greeted by website errors, lost orders, and long delays. Google also continued to take orders long after it had sold out of the initial stock. Many prospective owners still haven’t received their phones.

Google needs to team up with a company that has experience selling physical items in order to ensure this doesn’t continue to happen. When the Nexus 4 was sold out, Google linked to T-Mobile’s site so customers could buy the phone with a new service plan. When it was sold out there, T-Mobile stopped taking orders. What a novel concept.

T-Mobile is a good acquisition target not only because can it move devices, but it also has physical stores that can serve as a Google storefront where people can try before they buy. Having T-Mobile in its pocket offers Google retail opportunities beyond the Nexus 4. Consumers often gravitate to Apple because they can take their products into the Apple store when something goes wrong. Google could use T-Mobile’s physical presence to promote Android devices, Chromebooks, cloud service, and maybe one day, Google Fiber in more places.

T-Mobile needs rescuing

Google isn’t the only one that would benefit from a T-Mobile acquisition. The carrier was in dire straits when AT&T came calling, and things have only gotten worse since the merger was killed by federal regulators late in 2011. Financial results from the last quarter showed almost 500,000 subscribers jumping ship to other carriers. Revenues are also falling precipitously. A planned merger with MetroPCS likely won’t be enough to staunch the bleeding.

Even T-Mobile’s own leadership team has argued (quite well, in fact) that the company can’t survive on its own in the long term. There was plenty of gloom and doom to go around when the AT&T acquisition was still pending. The fundamentals haven’t changed, but Google can step in and maintain the four-carrier system by keeping T-Mobile in the game.

One of the main issues that prevented the AT&T&T deal from happening was that the larger carrier was going to swallow up the smaller one. Regulators felt that would reduce choice, especially when T-Mobile has traditionally had lower rates. Google has a better shot at getting an acquisition approved because it has the resources and motivation to make service more affordable — it can subsidize cell service just like it subsidizes unlocked phones.

You complete me

Google has reportedly been talking to Dish about acquiring spectrum licenses for a mobile network, but that’s only half the equation. T-Mobile has the cell towers to run a network, but is lacking in spectrum. It’s a perfect match. Google brings the cash and cellular bands, and T-Mobile has the infrastructure to deploy it. Google also has bundles of dark fiber crisscrossing the country, which might be of use in getting backhaul for 4G LTE up and running.

The launch of the Verizon-branded Galaxy Nexus last year was a learning experience for Google. Mountain View didn’t have the kind of control over updates and software on that device that it had with previous flagship phones. Verizon delayed updates, blocked Google Wallet, and generally made the LTE Nexus a second-class citizen. This is one of the principal reasons the Nexus 4 is HSPA+ only. To make future Nexus devices work, Google needs control.

Google clearly wants to push Android forward with as few carrier restrictions as possible, so why not own the carrier? Most carriers refuse to support unlocked devices fully; AT&T makes it remarkably hard to get a Nexus 4 running at top HSPA+ speeds. T-Mobile, on the other hand, has always been very pro-Nexus and pro-Google. The first few Nexus phones only supported T-Mobile 3G bands in the US, and the first Android phone (the G1) launched on T-Mobile. There is already a rich history of cooperation there.

T-Mobile’s current situation makes it ideal for a Google acquisition in another important way: there’s no iPhone on Magenta. All the other national players, and even some regional carriers have the iPhone now. If Google is going to use T-Mobile to push a pure Android experience and embrace unlocked devices, it doesn’t want to be in the position of supporting on-contract iPhone users that will be seeking support and services.

Google should just bite the bullet and do what is necessary to move the industry forward. The search giant has more than enough money in the bank to take T-Mobile off of Deutsche Telekom’s hands. It makes more sense than Google starting its own network, which would probably kill T-Mobile anyway. Google can get the spectrum; T-Mobile has the towers and retail experience. These companies already have suspiciously well-aligned goals.

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