Since you're probably going to be paying for a backup service for years, cost is an important factor to consider. All the services rounded up here are subscription-based, but they partition their features and fees differently, so it's worth comparing plans closely before committing to one. Most construct pricing tiers based on the amount of cloud storage included, however, or by the number of devices you can use with an account. A few services offer permanent free accounts, but those plans impose paltry storage limits or restrict key features to the paid versions. Watch out for file-size upload limits as well.