Every app that runs on iOS must be signed with a cryptographic certificate before it can be installed. This is enforced at install time and every time the app launches. If the signature is missing, invalid, or expired, iOS refuses to run the app.
What Exactly Is a Developer Certificate?
An Apple Developer certificate is a digital credential issued by Apple to members of the Apple Developer Program ($99/year). It contains:
- A public/private key pair — generated on your machine; the private key never leaves your control
- Your identity — tied to your Apple Developer account
- A validity period — typically one year from issuance
- Apple’s cryptographic signature — what makes iOS trust it
- A provisioning profile — a companion file that lists which device UDIDs the certificate is authorised to install apps on
That last point is critical for sideloading. Standard developer certificates require your device’s UDID to be registered in the provisioning profile.
What is a UDID? Your UDID is a 25-character alphanumeric identifier that uniquely identifies your iPhone or iPad. Find yours at udid.tech.
Types of Apple Developer Certificates
Development Certificate
Used to build and test apps on registered devices. Requires UDID registration. This is what CertDrop issues — an individual development certificate registered to your UDID.
Distribution Certificate
Used to submit apps to the App Store or distribute via TestFlight. Not used for sideloading.
Enterprise Certificate
Issued under Apple’s Developer Enterprise Program ($299/year) for organisations distributing internal apps. Does not require UDID registration. Frequently abused for mass sideloading — Apple aggressively revokes enterprise certificates used for this purpose.
How CertDrop’s Certificates Work
CertDrop purchases slots in Apple Developer accounts and registers your UDID into a provisioning profile tied to a valid development certificate. When you order:
1. You provide your UDID and email
2. Your UDID is registered to a provisioning profile in an active Apple Developer account
3. A certificate (.p12) and provisioning profile (.mobileprovision) are generated for your device
4. These files are delivered to your email
The certificate is valid for 360 days.
Developer Certificate vs Free Apple ID Signing
Many sideloaders know you can sign apps using a free Apple ID through Xcode without paying. Here’s why that’s a fundamentally different and more limited approach:
| Feature | Free Apple ID | Developer Certificate (CertDrop) |
|---|---|---|
| Certificate validity | 7 days | 360 days |
| App limit | 3 active apps | Unlimited apps |
| Requires Mac | Yes (Xcode) | No |
| Requires refresh | Every 7 days | Once per year |
| Signing tool | AltStore (requires computer nearby) | Feather, ESign, Scarlet (fully on-device) |
| Price | Free | $12 USDT |
Common Uses for Sideloaders
- Emulators and retro gaming — Delta, PPSSPP, RetroArch, and similar emulators
- Modified or patched apps — Ad-free versions, tweaked social clients, community builds
- Region-locked apps — Apps not available in your App Store region
- Developer tools and utilities — Apps removed from the App Store
- Personal app testing — Testing your own apps on a real device without a Mac
Is the Certificate Tied to Only One App?
No. Your developer certificate can sign as many apps as you want. You’re not buying a certificate for one specific app — you’re buying a credential that lets you sign any IPA on your registered device for the full 360-day period.