If you want a cloud-based file synchronisation and sharing platform you are really spoiled for choice; but one downside that Google, Microsoft, Dropbox and pals all share is that they're all controlled by somebody else.
If you want full control over your own data and don't mind running your own infrastructure to do it then two of the biggest players you'll come across are ownCloud and Nextcloud. What are the differences between these platforms, and which is best for you? Stay tuned, and let's find out!
I guess the first question to ask is: why, when many companies are moving to the public cloud, would you want the complexity of running your own private file sharing platform? Honestly, this isn't for everyone. Particularly when the likes of Microsoft 365 and Google Workspace come with working solutions straight out of the box; but there are reasons why doing it yourself can make sense.
The first is cost. Unsurprisingly it's often cheaper to do it yourself than pay someone to do it for you - assuming you have the capability to do so. This is a particularly big reason why hobbyists and home users do it - they don't have enterprise budgets to play with. It's the main reason I started using these solutions, myself.
I used to use Windows Live Mesh to keep my files in sync between different devices at home. That's been dead a while now so if you've never used it, it was a free peer-to-peer file synchronisation tool that sync'd between devices locally or over the internet. When Microsoft came out with OneDrive (then called SkyDrive) they discontinued Live Mesh and announced SkyDrive as a new tool to sync your files. Which meant it always went over the internet and now you had to pay for the cloud storage even if you didn't want the data to be stored online in OneDrive.
Other reasons you might want to host your own service are control and flexibility. If you have strict rules governing where your data can live then it might be a necessity. For most people that won't prevent them using one of the major cloud vendors, but you will still get more flexibility from running your own rather than picking a one-size-fits-all solution.
Back to my example at home. I have our various devices syncing back to a server. I also have some media services hooked into that, so if I drop a music file on my laptop it syncs and becomes available to stream to speakers around my house. If I record a video of my kids playing on my phone it syncs and could be played on the TV. All of the data is automatically backed up from the central location as well; meaning if a device fails, I delete something, or I get hit by ransomware; nothing is lost. I have some other services hooked into the synchronised data as well, but I'm not going to keep going down that rabbit hole. It's just an example of how I've been able to customise my self-hosted service so that not only is it cheaper and faster than using OneDrive; it also provides me with functionality that OneDrive can't.
Other reasons you might want to self-host are vendor lock-in and security. Self-hosting, particularly self-hosting using open source, makes it much less likely a vendor can bend you over any kind of proverbial barrel or leave you high and dry if they go bust. I mean it's not likely that Google or Microsoft will go bust, but there's also no telling what service they might just decide to kill off.
As far as security goes... I think "privacy" is a better way to put it. The vast majority of people who claim they're not using the cloud for security reasons are actually running systems less secure than the cloud ones they're avoiding. That doesn't necessarily mean they'd be any safer by moving the public cloud. For now let's talk more about ownCloud and Nextcloud, specifically.
ownCloud & Nextcloud Similarities
ownCloud and Nextcloud have more in common than they have dividing them. Both can be thought of as open source, self-hosted Dropbox alternatives. Both have paid support options available. Both share the same original codebase, and both were founded by the same person. There are some technical differences and this gap is likely to grow as the two projects diverge, but a lot of the differences are more philosophical or licensing related. If I quickly open the two platforms side-by-side you can see they share the same DNA.
So why did the founder quit his own company and fork his own code to start a new company? The ownCloud company was formed by the partnership of open source developers with a venture capital firm. Fundamentally, the problems stemmed from these two groups of people not seeing eye to eye. I'm not going to go into in detail because most of the information that has been made public is very one-sided and I don't think it would be fair for me to quote it as fact without hearing both sides of the story. You can look it up for yourself if you wish - it reads a bit like a soap opera and there's clearly a bit of lingering hostility.
I would summarize it as saying that the open source developers and the venture capitalists had different motivations, and failed to understand the other's; leading to a fair amount of internal conflict. This drove a wedge between the company and the community. It resulted in features getting blocked or removed; and some utterly ridiculous supportability problems like claiming Windows compatibility for the server despite never actually testing it, and it not actually working properly.
The result was that 12 members of the core development team, including ownCloud's founder, quit the company and formed Nextcloud. They forked the code and started developing their own version. It sounds like this was probably the best thing for both projects to put an end to the infighting, although clearly not a good thing for the employees of the U.S. company, ownCloud Inc., who lost their jobs in the resulting fallout.
In effect, NextCloud is the developers' original vision for ownCloud, and ownCloud today is the management or venture capitalist's vision for ownCloud. And for the record: neither ownCloud nor Nextcloud supports the server being deployed on Windows anymore. They came their senses On that one before the split occurred and decided if they couldn't make it work they should just be upfront about it.
Differences Between ownCloud & Nextcloud
So that gives you a very brief background. Back to the main question, though: which should you use? That probably depends a little on the features that matter to you, and whether you care about professional support.
The first major difference between the two is that Nextcloud is completely free, whereas ownCloud is only mostly free. ownCloud has proprietary features that are only available if you pay for their top-tier Enterprise subscription.
When Nextcloud split they re-implemented those Enterprise features as free and open source, meaning Nextcloud is fully featured whether you pay for support or just use the free version. If you're not looking for paid support this pushes my recommendation strongly towards Nextcloud because the functionality isn't being limited.
Another major difference between the two is that Nextcloud has expanded their focus from just file syncing. ownCloud is focused on being a file sync and sharing platform like Dropbox. That's what Nextcloud is known for, too; but they have extended their toolset to include conferencing and groupware solutions. They're aiming beyond Dropbox and more at something like Microsoft 365 or Google Workspace.
Now, in all honesty that may be their aim but those two are way ahead of Nextcloud right now. They're playing in very different leagues, but that's to be expected given the relative sizes of the companies involved. I don't personally use those Nextcloud features, so it's irrelevant to me; but if that is something you're looking for then ownCloud aren't going down that route. That's not a dig at ownCloud. It's not necessarily a bad thing to focus on doing one thing well and incurring less churn.
Open Source Communities
The last thing that matters when considering open source solutions is the community. Neither of these platforms exists by itself. There are people contributing to them. A quick look on GitHub shows more activity on the Nextcloud side of things. Now, it's a fair point that the number of commits doesn't tell the full story. Nextcloud could be making lots of smaller changes whereas ownCloud is making fewer but larger ones - that's an argument I've heard. If we compare the two graphs, though; we can see that around June 2016, ownCloud's activity dropped off quite noticeably whereas Nexcloud's didn't. So what happened in June 2016? Yup. That's when Nextcloud split. You can see the impact right there, and to me that doesn't look like Nextcloud simply make a larger volume of smaller changes. That looks very much like a lot of ownCloud's contributors jumped ship. The difference is less extreme now but Nextcloud still seems to be the one with the most activity.
The Google Trends graph also shows interest in Nextcloud of overtaking ownCloud around the start of 2018 based on web searches. Finally, the selection of apps available to plug into Nexcloud is larger than the equivalent list for ownCloud. Quantity is not necessarily an indicator of quality, of course; but these metrics taken together certainly make it appear that Nextcloud is a platform with the most activity, and potentially therefore the brightest future.
Now what if you're a business who wants the paid support option, and you're not interested in the additional features that Nextcloud has - you're only interested in the core functionality that is common to both? This is a little less clear-cut as each have different support plans that don't quite line up.
Nextcloud's public price list starts at 100 users whereas ownCloud starts at 25 users. For the sake of comparison I'll use 100 users on both. The cheapest option is Nextcloud's Basic support. Nextcloud's next option is their Standard support, but ownCloud's Standard support is priced just a bit above Nextcloud's Basic support and has a faster response time than both Nextcloud's Basic and Standard tiers. At that level ownCloud looks like better value, but remember you don't get the full feature set until you upgrade to ownCloud's Enterprise support. This compares to Nextcloud's Premium support and here Nextcloud looks better because they have options for tighter reaction times than ownCloud (although a wider range it has to be said) at a lower price.
More critically, Nextcloud's Premium support has an option for 24/7 support whereas ownCloud's Enterprise support doesn't appear to. That's a really weird omission, in my opinion. I'm honestly not sure that 12 hours a day, five days a week, actually counts as enterprise support, guys?
Of course this is all just me going off numbers on the websites. I have never used the support with wither of these organisations so I can't tell you what negotiation is possible, or what the quality of the support is like. That in itself is a very important consideration. Quality of support is absolutely critical when comparing the value you're getting, so if any of you guys have used the support services of either ownCloud or Nextcloud then comment below and let us know how you found it.
So let's bring this all together, then. Usually, these comparisons end up with a "well it depends on your situation". In this case I honestly think that in most cases Nextcloud looks like the winner. Depending on what you choose, you're either getting more features or you're getting a 24/7 support option.
The only scenario that jumps out where ownCloud is a better deal is if you want to pay for support, but only middling support, and you only care about the most limited set of core features; or maybe if you want paid support for less than 100 users. Certainly since I replaced my ownCloud server with Nextcloud I haven't looked back.
A couple of points I haven't touched on are performance and security. When Nextcloud started off they made a lot of noise about these two things, but I haven't come across anything in the way of independent analysis on it.
My own server was noticeably faster after switching to Nextcloud, but I also upgraded the version of PHP and implemented a Redis cache at the same time so that performance boost could have nothing to do with Nextcloud itself. I only mention these points because they come up in Google when you look for differences between the two platforms, but the information I've seen all seems to come from Nextcloud themselves, and I don't think we should just take their word on it unless it's been independently verified.
It's also worth mentioning that ownCloud have announced they're moving away from PHP and to the Go programming language, and they expect this to boost performance. It'll be interesting to see how the two stack up then, and whether Nextcloud follows suit.