APEX for iPhone and iPad
APEX Support
The master-bus chain, pocket-sized. Load a mix, hear the real engine on it, export when it is right. Below are the questions we are asked most. If yours is not here, email us and a person will answer.
How do I get a mix into APEX?
Two ways. Tap CHOOSE AUDIO FILE… on the opening screen — or LOAD… in the bar above the analyzer once you are past it — and pick a file from Files, iCloud Drive or another app; APEX copies it into your APEX folder so it stays openable. Or put the files there yourself: open the Files app, go to On My iPhone ▸ APEX, and drop mixes in. They appear in the list on the opening screen, and tapping one loads it. WAV, AIFF, MP3, M4A, AAC, FLAC and CAF are all read.
It says the file is too long
APEX currently holds the whole mix and the whole master in memory, so it caps files at **12 minutes**. Anything longer is refused with that message. A streaming render that lifts the cap is in progress; until it ships, bounce long-form material in sections, or master it on the desktop plugin.
What does AUTO MASTER actually do?
It measures the whole file — gated loudness, held true peak and a constant-Q tonal curve — and runs the plugin's own rule engine over that measurement to set the entire chain: weight, drive, EQ, the spectral balancer, the glue compressor and its ratio/attack/release, the multiband, clip and limiter, ceiling and output gain. It is measurement-driven, not a stored preset per genre. Pick a **Target** first — −14, −16, −10 or −8 LUFS — and a **Profile**: Neutral, Warm, Aggr or Club. The line under the button reports the moves it made that have no knob on the pocket screen, for example MULTIBAND 4-BAND · SPECTRAL BAL 60%.
Which target and profile should I pick?
−14 suits Spotify and YouTube, −16 matches Apple Music's reference, −10 and −8 are for loud club and DJ masters. Neutral leaves the tone as it found it, Warm leans the balance down, Aggr pushes harder into the clipper and limiter, Club is built for a big system. Start on −14 · Neutral, listen, then try another profile: AUTO MASTER re-runs on the same measurement instantly, so comparing is cheap.
How do I hear what it did?
Three controls sit in the header. **APEX ON** toggles the chain in and out at the same play position, so you hear the original against the master without losing your place. **MATCH** turns on loudness-matched monitoring, which is the honest comparison — a master that is simply louder always sounds better until you level it. **Δ** plays only what the chain is changing, which is the fastest way to catch a limiter working too hard.
Can I change what AUTO MASTER chose?
Yes — everything it sets is a normal control and it is all live. Weight is the hero fader; below it are Vintage Drive, Violet EQ, a 7-band Pro EQ whose curve you can drag, the Glue Comp with its Ratio, Attack and Release, the Multiband with per-band Tame/Open/Sat modes and Solo, the Spectral Balancer, HF · Image, and Clip · Limit · Out with Clip Mode and Limiter Character. Faders take a tap or a drag; pull away vertically for fine adjustment, and double-tap to reset one.
What formats does it export?
Tap EXPORT in the transport and choose **WAV 24**, **WAV 16**, **AAC 256** or **AAC 128**. WAV 24 is the one for distribution and archiving; the render is latency-compensated and dithered to match the depth you chose, and AAC is encoded by iOS itself. The master is written into the APEX folder as `<name>-APEX-master.wav` or `.m4a` — find it in Files ▸ On My iPhone ▸ APEX, where you can move it, AirDrop it or send it anywhere you like. An existing file is never overwritten.
What does APEX Pro unlock?
Everything you need to judge a master is free, forever: import, AUTO MASTER with every target and profile, the full chain, the meters and analyzer, A/B, MATCH and Δ. **APEX Pro is one payment of $9.99** — no subscription — and it unlocks **export** in every format. You hear the master in full before you decide to pay for the file. Reference match, saved revisions and album mode are coming to Pro in a later update.
I bought Pro but it is locked on my other device
Open the export sheet and choose RESTORE PURCHASE. APEX Pro is a one-time purchase tied to your Apple Account and restores on every device signed into it. If it still does not appear, check that the device is signed into the same Apple Account in Settings.
Does APEX upload my music?
No. There is no upload, no queue and no account — APEX has no server, makes no internet connections of its own and contains no analytics or advertising SDKs. Turn on Airplane Mode and everything except the purchase still works. It never asks for microphone access either. See the privacy page for detail.
Which devices are supported?
iPhone and iPad running iOS or iPadOS 16 and later. APEX runs on iPad today in the iPhone layout; a proper two-column iPad layout is on the way.
Contact
Email info@echelonlabs.llc. A person reads it, and we reply within one business day. Tell us your device, your iOS version and what you were doing, and we will come back to you. Privacy details are on the APEX privacy page.