Proton, a privacy startup best known for its Proton Mail encrypted email service, has just announced that its end-to-end encrypted cloud storage service is available starting today as an Android and iOS app. Proton Drive is available in both free and paid tiers, offering users a way to securely upload, store, and share files directly from their mobile devices.

Proton Drive’s end-to-end encryption ensures that only the user and the people they share with can access files — not even Proton itself can access the data without your permission. Users can send folders and files to anyone via sharing links (including non-Proton users) with options for passwords and expiration dates. Access can be revoked at any time, and metadata is encrypted, including file and folder names, creation dates, and thumbnails. You can also sync and preview files through the Proton Drive mobile apps.

The free version of Proton Drive provides 1GB of free cloud storage, which can be upgraded to 200GB of storage for $3.99 a month as a standalone subscription, or 500GB via the Proton Unlimited plan for $9.99 a month, which also includes Proton Mail, Proton Calendar, and Proton VPN. There’s no limit to file sizes.

And since Proton is based in Switzerland, the company claims that Proton Drive falls outside US and EU jurisdiction and isn’t subject to intelligence-sharing agreements like Five Eyes or Fourteen Eyes. The Swiss Constitution does include data processing regulations (Article 13), though it should be noted that some Swiss law only applies to Swiss residents. Other privacy protections such as the revised Swiss Data Protection Act (revDPA) however, can offer some protections for people living outside of Switzerland.

“While there have always been apps to upload and store files on your phone, they provide poor privacy, and data leaks from mobile devices are common,” said Proton CEO Andy Yen in a press release. “Proton Drive brings end-to-end encrypted file storage to iOS and Android and aligns with Proton’s mission to ensure that privacy tools are easy to use and freely available.”

Proton (not to be confused with the Linux compatibility layer of the same name) first launched Proton Drive for the web earlier this year, and claims that photos comprise around 50 percent of the one million files uploaded to the service so far.