Google's Project Fi cellular service is dropping its invite requirement. And to celebrate, the company just announced the deepest discount ever on the Nexus 5X. If you buy the phone through Project Fi and activate it, you can get the normally $349 Nexus 5X for just $199. The offer is valid from today until April 7, 2016.

The deal conjures up images of the two-year contract pricing carriers used to offer on phones, but Project Fi is a pre-pay service with no contracts, so it seems you can cancel at any time. The fine print only says, "You must then activate Fi service on the same account within 30 days of device shipment." We guess that you'd then be on the hook for a month of service, which at the minimum pricing will cost about $30. So even if you have no desire to join Project Fi, around $230 for a 5X while canceling Project Fi is still a deal.

Project Fi is Google's MVNO service that continually switches between Sprint and T-Mobile, while only charging you for the exact amount of the data you use, down to the megabyte. The service also combines all the best features of Google Voice, like visual voicemail, number forwarding, and the ability to send and receive SMS messages from any computer and via the Google Hangouts app. The only real downside is the extremely limited device compatibility—the Network switching feature means Fi only works on the Nexus 5X, 6, and 6P. Project Fi charges a $20 base fee for unlimited texting and calls, plus $10 per GB of data you use. We've got a full breakdown of the pricing here.

Google is killing the Project Fi invite program, but that doesn't seem like a huge deal. Getting an invite to Project Fi before never seemed like a huge challenge—we've only heard of customers waiting a week at most. Now Google seems ready to take things out of the "Beta" phase, and it's removing this one last barrier to entry.