How It Works

Filemo makes it possible to access files backed up using Arq by integrating them into the native iOS Files app. It accesses the encrypted backup data by using an open source server component and decrypts the files locally on your device. The server component can be run on a free Heroku instance or hosted on your own server. Currently backups using direct file access (SFTP) or S3 (Amazon, Wasabi) are supported.

Screens

Adding a Folder

To add a new Arq backup folder to Filemo, perform the following steps:

• Install and setup the server component by following the instructions in README.md.
  • You can host the server component yourself, or deploy it on Heroku (only available for S3 backups).
• In the Filemo app, tap “Add Server”. Enter the URL where the server component can be reached, e.g. https://mybackup.herokuapp.com/.
  • Enter the whole URL, including https:// and the trailing /.
• The app will automatically load all computers contained in the backup. Enter the access token when requested.
  • The access token can be configured in config.php.
  • When using Heroku, the access token is randomly generated. Access it under “Settings” > “Reveal Config Vars”.
• Select a computer. The app will automatically load all folders. Enter the encryption password when requested.
• Enable all folders you wish to access by toggling the corresponding switch.
• The folder is now accessible systemwide, e.g. using the preinstalled Files app.
  • If Filemo doesn’t appear as a location in the Files app, use “…” > “Edit”, then enable Filemo.

Is This Safe?

Arq encrypts and decrypts all data on device. The backups only contain encrypted data which can not be used without the encryption password. Filemo works the same way. The server component only provides encrypted data, and additionally requires an additional password to do so. More information about the server component can be found in its q&a section.

The encryption password is safely stored in the iOS Keychain like any other login information in your iOS device. It is also not synced among devices and Filemo never reveals the password in cleartext. The password is never sent over the network and is just used to decrypt data locally on the device.

However, be aware that once Filemo is connected to a backup, its content can be browsed with the Files app or any app that supports the iOS Document Browser. Handing someone your unlocked iOS device to someone becomes comparable to letting someone access your computer. Special caution is recommended in case the backups contain private keys for certificates or remote access.

The encryption password can be removed from the Keychain by changing it to an empty string (no password) in the app. After that, already accessed files might still reside unencrypted in the local cache. To purge the cache, tap the “Purge Cache” button or remove the server using the Filemo app.

Why Is There a Subscription?

Filemo is a side project I am working on in my free time. The main reason I am charging money for it is to see whether people are using it. Keeping up with adding additional technologies and mitigating potential future protocol changes takes time, and I want to know if it is worth doing.

The free version allows you to test whether Filemo works with your setup before spending any money. Also, I was able to price the subscription version much lower since it doesn’t have to include further development efforts.

What Versions of Arq Are Supported?

Filemo currently only works with backups created with Arq 5. Older versions might work, but are not tested. I will evaluate adding support for the recently released Arq 6 once its new backup format documentation is published.