In 2014 Proton mail started as an end-to-end encrypted email service offering secure and private email services. Proton mail is still live and going with the same dedication to privacy and security but the company has expanded its offering into cloud storage drive services.
Starting as a public beta at the end of 2020, Proton Drive is keeping its privacy and security policy philosophy with the new service. Proton Drive is the newest service besides Proton Calendar, Proton VPN, and Proton Mail.
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Drive has end-to-end encryption for everything on it including files themselves, filenames, folder structure, folder names, extensions, and file sizes. This means that you and only you can access your files. Servers are located in Geneva, Switzerland and they are under Swiss privacy laws making sure that your files are protected. Proton services in general are all open source so anyone can take a look at them to be sure that nothing is lurking under the hood. For now, sync is done either via the android app or web interface but the desktop client will come soon since currently, it is under development.
Sadly free plan of Proton Drive will give you only 1GB of storage which is much less than other services and sadly payments plans are also not so jaw-dropping going for $4 USD per month for a 200GB plan or with Proton ultimate subscription that will set you $10 behind but you will get 500GB of drive storage. Of course, if you value privacy for your files these options are good but if you do not mind that part other services have much better options.
All in all Proton Drive is a great cloud storage solution if you need privacy and well worth the investment. With the ultimate subscription, you will get enough space for most people and company needs with other services and guaranteed privacy and security, on the other hand, if you just need a large amount of cloud storage not caring too much about privacy other options are better.