Effective September 16, 2026
APEX Privacy
APEX is a mastering app for iPhone and iPad. It masters your mix on the device itself — there is no upload, no queue and no account.
What APEX does with audio
APEX works only on audio files you choose. It has no microphone access at all — iOS never asks for it, because the app does not request the permission. When you load a mix, APEX reads it into memory, measures it (loudness, true peak and a tonal curve), plays it through the mastering chain so you hear the result live, and renders the master offline when you export. All of that happens on your device, using the same processing as the desktop plugin. Nothing is sent to us or to anyone else at any point.
Files you import
Importing a mix with CHOOSE AUDIO FILE… copies it into your APEX folder and leaves the copy there. That is deliberate: the copy is what APEX plays, re-opens the next time you launch, and lists on the opening screen, and it is the reason a file picked from iCloud Drive or another app keeps working after that app's permission window closes. If the file you pick is already in the APEX folder, no second copy is made. The copy is yours to manage — APEX never deletes it. Delete it in the Files app whenever you want the space back, or delete the app to remove all of them at once.
The APEX folder
The APEX folder is a real folder in the Files app, under On My iPhone ▸ APEX (On My iPad on an iPad). You can drop mixes into it from a computer, from another app or over AirDrop, and they appear in the app's list. Because it is the app's Documents folder, anything you leave there — your imported mixes and the masters you export — is included in your iCloud or computer backups until you delete it. Exports are written to the same folder as `<name>-APEX-master.wav` or `.m4a`; APEX never overwrites an existing file, it adds a number instead.
Network
APEX has no server of its own and makes no internet connections of its own. It is built without networking: there are no analytics, advertising or crash-reporting SDKs, no remote rendering, no account and no telemetry. The only network traffic is Apple's — StoreKit checking your purchase and the current price with the App Store, iCloud downloading a file you pick if it is not already on the device, and a link you tap opening in your browser. APEX works with the device in Airplane Mode, which is the plainest demonstration of this.
What APEX stores on your device
The settings of the chain — every knob, the target and profile you last chose, the segment choices and your preferred export format — and the file name of the last mix you loaded, so the app can reopen it. They live in the app's own storage on the phone, are included in your device backup, and are removed when you delete the app. Your imported mixes and exported masters live in the APEX folder, described above, and stay until you delete them. None of it is sent to us or shared with anyone.
Purchases
APEX Pro is a one-time in-app purchase processed by Apple through the App Store. Echelon Labs LLC never receives your name, payment details or address; Apple's own privacy policy governs the transaction. APEX checks your purchase status and the current price through Apple's StoreKit framework, which contacts the App Store — never a server of ours. RESTORE PURCHASE asks Apple for the purchases already on your Apple Account.
Data we collect
None, in the app. APEX does not collect personal data, usage data, identifiers, location, contacts or anything else, and our App Store privacy label states "Data Not Collected". This website is separate: echelon.audio measures its own pages with a first-party beacon and the Meta Pixel, as our site privacy notice explains. The one thing we do receive is what you choose to send us: if you email support, we hold that message and whatever you put in it — usually your device and iOS version — for as long as it is useful to resolve the case, and we delete it on request.
Keeping and deleting your data
Everything APEX keeps lives on your device, so you decide how long it is kept. Mixes you imported and masters you exported stay in the APEX folder until you delete them in the Files app; your chain settings and the name of the last-opened mix go when you delete the app. Your Pro purchase is held by Apple against your Apple Account, not by us, and RESTORE PURCHASE brings it back on any device you sign in to.
Children
APEX is not directed at children and does not knowingly collect any information from anyone, including children.
Changes and contact
APEX is published by Echelon Labs LLC, the company behind Echelon Audio. If APEX ever changes how it handles data, this page will be updated and the app's version notes will say so.
Contact
Questions about this policy: info@echelonlabs.llc.