I love syncing data. I really do. Its simplified life from copying files to a flash drive to move from one computer to another. And then when I adopted my first smartphones (Palm Centro, Palm Pre) it was a hassle carrying data with me. I would take a picture and then need a data cable to download it to my computer.
Sync and backup services automate much of that now. I like to complicate things a little further though. I require services that work not only with Windows and Android (which most, if not all, do) but also with Linux. Specifically, I run Ubuntu and Fedora so some apps like Ubuntu One (which I like) don't work fully for me. Thus, my great sync service face off.
AdeptCloud lures users in with promises of free "unlimited files of unlimited size." The trouble is that its not truly unlimited. This service does not offer free online storage like the others do. Its purely for syncing files and it relies on the storage space on the user's systems. It does, however, work on Linux, Mac, and Windows as well as Android and iOS. It will not work on a mobile device alone. A desktop system is required to store the files and the mobile device will retrieve them from there. AdeptCloud says it will create a "mesh of storage" for easy access.
I am already disappointed with this service. When I tried syncing the files to Ubuntu, I couldn't download anything. Why? Because they are on my desktop at home that's turned off. I was also disappointed by the installation process. Dropbox can offer DEBs and RPMs but all adeptCloud offers is a lousy RUN file.
Online storage is available to business customers for a fee of $10 per month covering up to 10 employees.
I like Box. Mostly. I've taken advantage of the free 50 GB promotion they've had at one time or another. Those 50 gigs make Box very like-able for me. What don't I like? No native Linux support and poor sync support for Android. Other apps will automatically upload new photos from my phone. Not Box. Box can be synced with Linux using webdav. Still not on par with a native application. I keep Box around to backup the files I don't need as often.
Copy offers pretty much everything I'm after: lots of free space (I have 17 GB now), Linux support (in the form of a tarball), an Android app, Windows support, and auto photo uploading. Given that this doesn't have the space that my Box account does, I wouldn't do a backup here. This will likely become my main service. Copy offers 5 GB for each referral (that's 5 for me and 5 for you if you sign up) and doesn't appear to have a limit. Its cheap too. For $100 a year, you can get 250 gigs.
This is the biggie. Dropbox is probably the most popular service around. It does offer strong Linux support (32- and 64-bit RPM and DEB) and a capable mobile app with automatic photo upload. Dropbox fails when it comes to capacity. It comes with 2 GB standard and referrals will only earn you 500 MB apiece. You also top out at 18 GB of free space. Paid upgrades start at $100 a year for 100 gigs. Because of several security gaps in the last few years, I don't keep anything too important or private on Dropbox. It is still a strong syncing service and an easy way to share files.
Anyone with a Google account already has a Drive whether or not they use it. I love Drive for editing documents and I backup all of my school work to it. It has Android and Windows apps which sync all of the documents to my computers. Drive also comes with 15 GB of storage that's shared with Gmail and Google+ Photos. However, anything created in Drive (Docs, Sheets, Slides) and pictures smaller than 2048x2048 do not count towards storage.
I have a rant against Google here. Google is a company that is basically built on Linux. Its servers run Linux. Its desktops are limited to Linux or Mac (special permission is required at Google to use Windows). Android and ChomeOS are built on Linux. Yet for some odd reason, they have not released a Drive app for Linux yet. Personally, I feel they could pay back some of their success with a few native apps for Linux.
There are alternative solutions here. I've tried Grive and Insync. Grive worked but it requires an active Internet connection. Insync is in beta for Linux and once out of beta will cost a one time fee of $10. I still utilize Drive though. My photos auto upload to Google+ and I keep my school work in Drive. Cost wise? 100 GB at $5 a month ($60 a year).
This is a service I want to use. It plays well with Android and my photos. It integrates tightly with Windows 8 but is still fine on 7. It comes with 7 gigs of free storage but the upgrades are dirt cheap. How about 20 GB/$10 a year, 50 GB/$25, or 100 GB/ $50? That's on top of the free 7. I also appreciate that Skydrive gives the user the option to select MS Office XML format or OpenDocument Format for files that are created in Skydrive. The ability to create documents directly from Skydrive a la Google Drive is pretty awesome. This has a big advantage over Google because it creates the documents in the MS format.
Skydrive is lacking for me in the Linux arena. There's no Linux support since it is, after all, a Microsoft product designed for Windows.
One is designed by Canonical for Ubuntu. Its made to backup Ubuntu and sync files between Ubuntu, Windows, Mac, Android, and iOS. It generally does this well. It auto uploads photos from Android quickly but the ability to preview the photos on Android is poor in comparison to Dropbox. It comes with 5 GB for free with 20 GB packs available for $30 a year.