Comparison

RackDocs vs Sunnandaeg

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

RackDocs

Document your modular synth modules with photos, notes, and AI assistance. Track switch positions, LED behavior, and multi-step operations. Sync across devices and access a community library of module documentation.

Highlights
  • Photo-based module documentation
  • AI annotation extraction from manuals
  • Multi-context documentation
  • LED behavior tracking
  • Switch position guides
  • Community library access
  • Offline mode and iCloud sync
Features
Read full description

Remember When You Knew What Everything Did? You know the feeling. You're three hours deep into a patch on your Eurorack (or Buchla, or Serge, or 5U rig), riding that creative flow, when you can't remember if that switch toggles the quantizer or unlocks some hidden LFO mode you discovered last month at 2 AM. Or worse, you finally saved up for that complex module everyone raves about. The manual is 87 pages of dense tables. There's a switch upper left. And three knobs. A mysterious LED that blinks in morse code. You patch something, it sounds incredible... then forget how you got there. RackDocs was born from exactly these moments. Built by someone staring at their rack, trying to remember what switch position enables through-zero FM. YOUR RACK, ACTUALLY DOCUMENTED Forget dusty manuals and half-remembered forum posts. Take a photo of your module, mark it up with everything you discover, build your own personal wiki. Every hidden feature. Every switch position. Documentation on your terms. Works with Eurorack, 1U, 5U/MU, Serge, Buchla, and more. BUILT FOR EXPLORATION • NEW: AI annotation extraction—point at a manual or PDF, get all controls identified automatically • Photo-based—faceplates are already the perfect reference • Auto-snap to controls (tap near a jack or knob, circles detected automatically) • Smart image editing (crop that cluttered desk out) • Import specs from ModularGrid (why type HP and mA manually?) • Multi-format support (3U, 1U, 5U, Serge, Buchla—we don't discriminate) • Annotation tools that make sense DOCUMENT EVERYTHING YOU DISCOVER • 12 annotation types for every control (not just "knob goes brr") • Multi-context documentation (Normal Mode vs. Secret Alt Firmware Mode) • LED behavior tracking (solid/blinking/pulsing/existential crisis) • Switch position guides (up = quantized, down = chaos, center = ???) • Multi-step operation notes (tap this while holding that) • Copy/paste annotations CURATED NEWS FEED • Eurorack news, videos, and new module releases - all in one place COMMUNITY LIBRARY • Many modules documented by fellow patch nerds • Share your discoveries • Vote on documentation (yay or meh) • Verified accounts prevent random chaos SYNC EVERYWHERE, WORK OFFLINE • iCloud sync across iPhone, iPad, and Mac (patching happens everywhere) • Full offline mode (studio has no WiFi anyway) • Your data stays yours (unless you decide different) ORGANIZE THE BEAUTIFUL CHAOS • Search by name, manufacturer, or custom tags • Sort however your brain works • Export cheat sheets as PDFs or images (print them, share them, flex on Instagram) PRICING Start free with 5 modules, 5 community downloads and 5 exports. Try it, see if it fits your workflow. If you like it: • Monthly - No commitment. Cancel anytime. • Yearly - Best value. Less than a patch cable. • Yearly Supporter - Locks your price forever. New features, same rate. For those who hate price increases. Supporter badge! • Lifetime - Pay once, own forever. No subscriptions, no renewals. Support indie development, not investors. Why subscriptions? Servers cost money. Development costs time. This keeps the lights on and lets me build what you need. WHO MADE THIS? A modular enthusiast tired of scribbling notes at 3 AM. Someone who's bought complex modules, discovered secrets over weeks, then forgot everything after a creative break. PERFECT FOR: • Beginners drowning in manuals and tutorials • Live performers needing instant reference (no PDFs on stage) • Collectors managing systems too big to memorize • Gear heads who RTFM and want to share knowledge • Anyone who's thought "this module did something cool last week" Download RackDocs. Document your discoveries. Patch with confidence. Your rack is unique. Your documentation should be too. Screenshots show the app documenting third-party hardware. Module designs © their respective manufacturers. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

About

Sunnandaeg

Features
Read full description

Sunnandæg is a single-voice instrument. One sine oscillator runs through three folding stages, and the end of that chain is wired back into the oscillator's pitch, sync and FM. There is no keyboard and no sequencer. You play it with four XY pads, the camera, and the tilt of the device. Raise the feedback and the folding starts folding itself, and the same gesture stops giving the same answer. SIGNAL Three folding stages: a squaring drive, a triangle wave folder, a full-wave rectifier. Their order can be swapped. A feedback network of three lines, each taking a stage output, the filter, the resonant EQ, or white or pink noise, and sending it back into a folding stage. FILTER Twin Peak — two resonant peaks with their own positions, range and band mode. Push Q far enough and the filter sings on its own. Rez EQ — eight resonators on fixed frequencies from 60 Hz to 9.8 kHz, each driven by its own source, able to feed both itself and the oscillator. MODULATION A sample and hold with a slope output and a comparator gate. An eight-stage shift register with a stepped three-tap mode. Two LFOs, the camera, and tilt. Every source chooses its own destination: pitch, filter, any folding stage, feedback or pan. EFFECTS Delay, reverb, phaser and chorus, each with two parameters and a modulation source, plus a random switcher. MICRO SOUND Record through the microphone and play the material back in grains, mixed against the dry voice. ALSO Twelve preset slots. A gesture recorder that replays your pad movements. MIDI in and out. An eight-band EQ, a compressor, a leveller and an output ceiling. Nothing leaves the device. The app makes no network connections at all.

Screenshots

RackDocs4 screens
Sunnandaeg4 screens

Verdict

The call

The clearest difference is price: RackDocs at Free against Sunnandaeg's $4.99. Sunnandaeg's advantage is in-app purchases (none vs 4). On update cadence, ads, device support and iOS requirement there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

RackDocs is free to download; Sunnandaeg costs $4.99 up front. RackDocs sells 4 in-app purchases, starting at $0.99 per month. Sunnandaeg asks for nothing beyond the download.

UpkeepUpdate frequency

RackDocs ships an update weekly, Sunnandaeg every 5 days. The most recent releases landed on November 9, 2026 and November 8, 2026 respectively.

Scorecard2 real differences · 8 level
RackDocs versus Sunnandaeg: the parameters behind the verdict, then further details
ParameterRackDocsSunnandaeg
PriceFree — better$4.99
Rating5.0 (4 ratings) — better—
Positive reviews100.0% of reviews—
Number of ratings4 — better—
Update frequencyWeeklyEvery 5 days — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFreemium—
DevicesiPhone, iPadiPhone, iPad
Requires iOS18.017.0 — better
Further details — not scored
Size31 MB2 MB
Age rating4+4+
DeveloperTheMMKei Odaka

In-app purchases

4 purchases

RackDocs

Subscriptions3
  • Monthly Subscription$0.991 Month
  • Yearly Subscription$3.991 Year
  • Yearly Supporter$8.991 Year
One-time1
  • Lifetime Access$44.99
None

Sunnandaeg

No in-app purchases

Questions

Is RackDocs free?
RackDocs is free to download, with in-app purchases available.
Is Sunnandaeg free?
Sunnandaeg costs $4.99, with no in-app purchases.
Do RackDocs or Sunnandaeg have ads?
Neither RackDocs nor Sunnandaeg shows ads.
Which is updated more often, RackDocs or Sunnandaeg?
RackDocs ships an update weekly, and Sunnandaeg every 5 days. Most recently, RackDocs was updated on November 9, 2026 and Sunnandaeg on November 8, 2026.

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