Scarlet & Developer Mode on iOS: What to Enable
Since iOS 16, Apple has put a gate in front of sideloading that did not exist before: Developer Mode. Some install flows stop dead without it, others never ask for it — and the confusion produces one of the most common Scarlet support questions we see: “Do I need to turn Developer Mode on, or is something else wrong?” This guide gives the honest answer. For Scarlet’s standard install, Developer Mode is not required. For several neighbouring tools and methods, it absolutely is. Here is how to tell which situation you are in, how to enable it when you truly need it, and how to fix the “Developer Mode Required” message.
What Developer Mode Is
Developer Mode is a device-wide switch Apple introduced in iOS 16. With it off (the default), iOS refuses to run apps that were installed through developer channels — locally built apps, certain sideloading methods, and apps signed in particular ways — even if they were installed successfully. Turning it on is a deliberate, slightly buried action that ends with a restart and a confirmation prompt, by design: Apple wants enabling it to be an informed choice, because it does relax one layer of the platform’s defences. It does not disable the App Store’s protections, sandboxing, or certificate checks; it simply permits developer-installed software to launch.
Do You Need Developer Mode for Scarlet?
For the standard Scarlet experience — installing Scarlet with its enterprise certificate and trusting the profile — no. Enterprise-signed apps run under the enterprise trust system, which is separate from Developer Mode. If your Scarlet install is asking about Developer Mode, one of these is usually true instead: the prompt is coming from a specific app or method inside your wider setup, or an error is being misread. This table separates the cases:
| Situation | Developer Mode needed? | Why |
|---|---|---|
| Installing and using Scarlet (enterprise certificate, trusted profile) | No | Enterprise trust governs these apps, not Developer Mode |
| Apps installed through Scarlet with that same enterprise certificate | No | Same enterprise trust system — if these fail, suspect the certificate, not Developer Mode |
| AltStore/SideStore-style installs signed with your own Apple ID for development | Yes, on iOS 16+ | Development-signed apps are exactly what Developer Mode gates; see our Scarlet vs AltStore comparison |
| LiveContainer and other container/JIT-adjacent tools | Often, depending on the tool and method | Several of these run apps through development-style pathways; our LiveContainer guide covers its specifics |
| TrollStore-installed apps | No | TrollStore uses a different mechanism entirely — see the TrollStore explainer |
| An app shows “Developer Mode Required” on launch | Yes — for that app | The message is literal: that particular app was installed in a way iOS classifies as developer distribution |
How to Turn Developer Mode On
- Open Settings → Privacy & Security.
- Scroll to the bottom and tap Developer Mode. (If the option is entirely absent, it appears after the device has something developer-related installed or attempted — install the relevant app first, then look again.)
- Toggle it on and confirm.
- Your iPhone will restart. This is mandatory, not a glitch.
- After the restart, unlock the phone and confirm the final prompt asking whether you really want Developer Mode enabled.
Total time is a few minutes. Note what the process is telling you about Apple’s intent: the restart-and-confirm design means no app or website can switch this on silently for you — if anything ever claims to enable it remotely, close the page.
Fixing “Developer Mode Required”
If an app refuses to launch with this message: enable Developer Mode with the steps above, restart, and try again — that resolves the genuine cases. If the message appears for an app installed through Scarlet’s enterprise certificate, something else is wrong, because that channel does not use Developer Mode at all: the likelier causes are a revoked certificate or a verification failure, which present as crashes and integrity errors rather than this prompt. Our guides to the integrity error and the untrusted developer message cover those paths — matching the fix to the actual message saves a lot of random toggling.
Is Leaving Developer Mode On Safe?
Mostly, with eyes open. It permits developer-installed apps to run; it does not switch off sandboxing, code signing, or certificate revocation, and your App Store apps behave identically. The honest caveat is that you have removed one checkpoint whose entire purpose is to make you think before running software from outside the App Store — so the discipline has to come from you: only install apps from sources you have reason to trust, which is the same advice that applies to sideloading generally (our Scarlet safety overview works through it). If you finish with the tool that needed it, turning Developer Mode back off is one toggle in the same place, and doing so costs nothing.
Developer Mode on iOS 26
The system still works the same way on current iOS: off by default, enabled per device in Privacy & Security, restart required. Scarlet’s own install flow on iOS 26 remains an enterprise-trust flow, as covered in our Scarlet on iOS 26 guide — if you are setting up a mixed toolkit (Scarlet plus a signer plus a container app), expect to enable Developer Mode once for the development-channel tools and then forget about it.
One More Distinction: Developer Mode vs Developer Accounts
The similar names cause a persistent mix-up worth clearing. Developer Mode is the on-device switch this guide is about — free, instant, and present on every iPhone running iOS 16 or later. A developer account is Apple’s paid program, and it matters to sideloading for a different reason: it is where your own long-lived certificates come from, the ones you can import into Scarlet or a signer as we describe in the certificate import guide. You can have either without the other. Enterprise-signed Scarlet needs neither the switch nor the account; an Apple ID signer needs the switch but not the paid account; your own-certificate setup uses the account’s certificates but still does not need the switch. Keeping those three lanes separate will save you from most of the contradictory advice in sideloading forums, where “developer” is used for all of them interchangeably.
FAQ
Does Scarlet require Developer Mode?
No. Scarlet installs with an enterprise certificate and runs under the enterprise trust system, which is independent of Developer Mode. If everything in your setup is enterprise-signed, you never need to touch the Developer Mode switch.
Why don’t I see Developer Mode in Settings?
The option often stays hidden until something on the device needs it — typically after you install or attempt to run an app through a development channel. Install the relevant app first, then check Settings → Privacy & Security again, right at the bottom.
Is Developer Mode the same as jailbreaking?
No. Developer Mode is an official, Apple-provided setting that simply allows developer-installed apps to launch. It does not modify the system, bypass code signing, or void anything in the way a jailbreak does — and it can be switched off again in seconds.
My app says “Developer Mode Required” but Scarlet works fine. Why?
Because the two are on different tracks. That app reached your phone through a development-style install (an Apple ID signer, a container tool, or similar), which iOS 16+ gates behind Developer Mode. Scarlet’s enterprise-signed apps are gated by profile trust instead.
Can a website or profile enable Developer Mode for me?
No. Enabling it requires the on-device toggle, a restart, and a post-restart confirmation, all done by you in Settings. Anything claiming to turn it on remotely is a scam pattern — a good rule for sideloading generally.
