Proton, the Swiss-based pro-privacy productivity app maker, has a new feather in its cap after bringing document creation, editing and collaboration capabilities to its secure cloud storage offering. The launch of Docs in Proton Drive, as the new product is branded, follows its acquisition of secure note-taking app Standard Notes in April.

Proton launched Proton Drive, its end-to-end encrypted (E2EE) cloud storage service, back in September 2022, starting with web support and expanding to mobile later the same year.

The new collaborative document features are being made available inside Proton Drive, further extending the company’s trademark pitch of robust security to another key productivity tool for both information workers and individuals alike.

Proton is pitching the combo of Docs in Proton Drive as a secure and privacy-focused alternative to Google Drive and Docs, given that the latter’s rival products lack Proton’s flagship zero-knowledge architecture.

“This landmark addition to Proton’s suite of privacy-focused products provides a robust alternative to existing document editors like Google Docs, ensuring that privacy and security are paramount — without compromising on vital features,” the company wrote in a blog post.

E2E encryption refers to a technical architecture whereby the entity providing the software is unable to access user content since it does not hold encryption keys. This allows Proton to make a trustless pledge of privacy that offers a clear differentiation versus data-dependent business models, such as Google’s.

“Docs offers the same level of encryption as Proton Drive, meaning all the contents are protected by E2EE,” a company spokesperson confirmed to TechCrunch. “Even changes and keystrokes are encrypted, as well as file names and file paths.”

“Building collaborative documents that retain E2EE was incredibly difficult, and something that we haven’t seen anyone else doing on the market. It involves key exchange and synchronized key information, plus the ability to invite people to collaborate, and revoke those permissions, as well as to share documents privately,” the company also said.

Proton says it will update its website in the next few weeks to go into more detail about how Docs works behind the scenes. The company notes it had already launched enhanced sharing features on Proton Drive a few weeks ago in anticipation of this launch.

Per Proton, Docs in Proton Drive includes popular and “essential” features, such as full support for markdown and rich text, code blocks and checklists. It also confirmed compatibility for multiple file types, including Microsoft .docx, and the ability to embed images in documents.

Collaboration features include the ability to add and reply to (and resolve) comments, and see who else is viewing a document in real time with “collaborative cursors.” Invites to collaborate on docs are also supported; participants without a Proton account will be prompted to create a free account to gain access, which could help it drive additional registrations and stoke its growth.

In line with Proton’s freemium ethos, the new document features can be accessed for free through Proton Drive, which offers up to 5GB of free storage. After this threshold, users wanting to tap the document capabilities will need to upgrade to a paid tier of Drive.

More features are in the development pipeline. Proton said its roadmap will aim to enhance user experience and productivity starting with more powerful collaboration tools for teams. Given Proton’s security pledge, it’s pitching Docs in Drive at businesses that are subject to high data protection compliance requirements, such as those in industries like healthcare, media, finance and legal. However, individual users can benefit, as well.

The company confirmed that code for docs will be open-sourced “soon,” allowing for independent auditing and verification of its security claims.

In a further reassuring step for users, last month Proton announced it’s transitioning to a nonprofit foundation structure model, with the new foundation becoming the main shareholder in the (for-profit) business. It said this governance change is designed to safeguard its pro-privacy mission for the long term by enabling it to be self-sustaining and independent of other commercial agendas.

The app maker, which was founded a decade ago as an E2EE webmail service (ProtonMail), has grown usage over the years by expanding to offer a suite of pro-privacy freemium productivity-focused apps, including its cloud storage service, along with a calendar app, VPN and password manager tool.

Proton now reports more than 100 million user accounts in total, with 500 employees keeping all its tech ticking over.