Legendary jailbreak hacker Comex is assisting iMods with a Cydia Substrate alternative


It’s been a long time since we’ve heard Comex’s name be associated with jailbreaking, but he’s back, and in a fairly large and controversial way. The creator of JailbreakMe is working with the team behind iMods—a Cydia alternative—to develop a Mobile (Cydia) Substrate replacement called Substitute. On the surface, it may not sound like much, but this could have far-reaching consequences on jailbreaking as we currently know it.


The iMods team released a trailer late last year highlighting the UI of their Cydia alternative. Visually, it looks appealing, but like so many of these so-called Cydia alternatives, shipping something that works for a massive number of users is a whole different ballgame.

But having Comex on their side is definitely a step in the right direction. There’s no question that he has the aptitude and ability to pull of a Cydia Substrate replacement given adequate time to work on it.

Cydia Substrate

Why is having a Substrate alternative so important for an alternate Cydia Store? Cydia Substrate is the code injection platform used to hook functionality into existing apps. Jailbreak tweaks use Cydia Substrate to hook into apps to make them do things that they weren’t originally designed to do. Since Cydia Substrate is closed source, an alternative needed to be made for anyone serious about supplanting Cydia. Substrate also provides important safety features like Safe Mode, though Comex’s alternative doesn’t yet include a working safe mode.

Why is he doing it? Comex listed three reasons for his work on Substitute via Substitute’s GitHub page. The first two reasons were more technical, but the third reason contains what I believe is his primary motivation behind this project:

The way I see it, jailbreaking is fundamentally about taking something closed and fixed and opening it up to hacking and modification: perhaps allowing a mess to be made, but quite possibly ending up with something unique and different. This ideal of openness is very similar to that of free software, and I therefore believe that it’s in the spirit of jailbreaking to make as much low-level stuff open as possible, both for inspection and modification by curious users

At the end of the day, Comex isn’t naive about the different layers of complexity that make up this community. He outright acknowledges that his work will inevitably cause some drama.

Me and Saurik

In the past, Saurik himself wrote a lengthy response to iMods’ interest in becoming a Cydia competitor or at the very least, a Cydia alternative. In a piece called Competition vs Community, Saurik spells out his reasoning behind his decision making. He then suggests that competition is the exact opposite of community, and alludes to the idea that he could do something else if a major Cydia competitor began to encroach on his territory.

Personally, I can see it both ways. Yes, jailbreaking has always been about opening up the walled-garden that Apple subjects its software to. Yes, there is a strong sense of community within the jailbreak circles, and people like to help each other, break things, build things, learn, etc. I don’t blame Comex for wanting to get his hands dirty so to speak, but I can see Saurik’s point of view as well.

One point from Saurik’s 5,000+ word essay really struck me, though:

I am not “just a storefront”. However, if you compete with me on the storefront, you not only indirectly affect my interest to keep working in the community, but you directly affect my ability to spend time doing so… Because if you are, you aren’t just picking a fight, you are walking into one you can’t win: where on the one side is losing quickly, and the other side is still losing, it’s just losing a little bit later, after the infrastructure you are relying on crumbles and key parts of the developer and support community (first- and third- party) disappear.

That sounds like mutually assured destruction to me, albeit, it’s not something that will happen immediately. The question is, if Saurik decides that one day enough is enough, who will step up and take his place? Who would be able to fill those shoes? It’s an interesting thought to ponder.

At any rate, Comex’s code isn’t in the alpha stages yet, and it remains to be seen if iMods can pull of something that’s even within the realm of Cydia from a stability, speed, and functionality standpoint. It’ll be a while before everyday users will be able to get their hands on a workable build of iMods with Substitute in tow. If and when that day arrives, we’ll be sure to bring you an overview of it.

What do you think about the prospect of having a true Cydia alternative? Share your thoughts down below.