Comparison

GRAB EM Field Synth vs Pocket Lofi

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

Head to head
About

GRAB EM Field Synth

This experimental synthesizer uses your iPhone's magnetic sensor to capture ambient electromagnetic waves and transform them into sound. Explore unique soundscapes by "playing" the electromagnetic noise from everyday electronics like power adapters and Wi-Fi routers.

Highlights
  • Electromagnetic wave to sound conversion
  • Multi-layered sound engine
  • Sensor-linked synth voices
  • Camera-driven tremolo effect
  • Bitcrush, comb filter, reverb, stutter effects
  • Ableton Link tempo synchronization
  • 3D point cloud frequency spectrum visualization
Features
Read full description

GRAB uses the magnetometer in your iPhone as an antenna. It receives the electromagnetic noise around you and turns it into sound in real time. Power adapters, motors, displays, Wi-Fi routers — the invisible field they radiate becomes the source material, and you play it the way you would play a field recording. Move to a different room and the instrument sounds different. SOUND ENGINE • Five ETHER-inspired layers: mains hum / PWM buzz / static hiss / high squeal / pulse train • Three sensor-driven synth voices: saw / square / noise • With the camera on, light falling on the lens drives a tremolo across level and timbre EFFECTS • CRUSH — bit crusher with sample-rate reduction • COMB — comb filter with feedback • REVERB — multi-tap reverb with shimmer • STUTTER — BPM-synced gate • MUTE — momentary kill switch; tap it repeatedly to articulate a tremolo by hand • HOLD latch on every effect pad, from the button or a second finger ABLETON LINK • Automatic tempo sync with Live, Logic and other iOS music apps • STUTTER locks to the Link tempo at 1/4, 1/8, 1/16 and 1/32 • Uses Ableton's official Link settings panel • Plays alongside other audio apps rather than interrupting them VISUALS • 3D point-cloud frequency spectrum • Spectrum bar mode • With the camera on, a grayscale image sits behind the field in depth WAYS TO PLAY • A field-sound tool: walk it past appliances and hear the timbre shift • An atmospheric noise source to drop into a live set • A platform for experimenting with electromagnetic noise music PRIVACY All audio is processed on the device. Nothing is recorded and nothing is sent anywhere. Ableton Link communicates only within your local Wi-Fi network.

About

Pocket Lofi

Listen to endless, original lofi and chillhop music across five distinct moods. Enjoy seamless looping, background playback, and a sleep timer. Unlock all stations with a subscription or lifetime purchase.

Highlights
  • Original lofi and chillhop loops
  • Five distinct music stations
  • Seamless, endless looping
  • Background playback with lock-screen controls
  • Sleep timer with fade-out
  • Favorite loops
  • Hand-drawn artwork
Features
Read full description

Lofi is a little night room you can carry in your pocket — original lofi and chillhop loops playing endlessly, like a radio station that never asks anything of you. FIVE STATIONS, FIVE MOODS • Focus — deep work, warm keys • Rain — storms against the glass • Sleep — slow waves for soft nights • Chill — lazy afternoons, golden light • Groove — jazzy chillhop rhythms PRESS PLAY, PUT IT DOWN • Every track loops seamlessly, forever — no endings, no interruptions • Join each song mid-stream, like tuning into live radio • Plays in the background with full lock-screen controls • A sleep timer that fades you out slowly when you're already gone • Favorites for the loops you can't let go of • Hand-drawn artwork for every single track ORIGINAL MUSIC Every loop is original, made for this app — warm tape hiss, soft piano, brushed drums, rain on glass. No playlists to manage, no decisions to make. Just a lamp, a window, and something playing quietly. Free to listen with a taste of every station. Unlock the whole room with a monthly subscription or a one-time lifetime purchase. Questions? contact@theapptor.com SUBSCRIPTION & PURCHASES • Premium Monthly — $2.99 USD per month, auto-renewing. • Lifetime — $24.99 USD, a one-time purchase (not a subscription). Payment is charged to your Apple Account at confirmation. A monthly subscription renews automatically unless it is cancelled at least 24 hours before the end of the current period. Manage or cancel anytime in your Apple Account settings. Privacy Policy: https://amian.github.io/lofi-privacy.html Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

GRAB EM Field Synth4 screens
Pocket Lofi4 screens

Verdict

The call

The clearest difference is review sentiment: GRAB EM Field Synth at 100% against Pocket Lofi's 0%. GRAB EM Field Synth also leads on in-app purchases (none vs 2) and ads (none vs shown). Pocket Lofi's advantage is price (Free vs $3.99). On 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

Pocket Lofi is free to download; GRAB EM Field Synth costs $3.99 up front. Pocket Lofi sells 2 in-app purchases, starting at $2.99 per month. GRAB EM Field Synth asks for nothing beyond the download.

UpkeepUpdate frequency

GRAB EM Field Synth ships an update daily, Pocket Lofi every 5 weeks. Both last shipped on October 31, 2026.

Scorecard6 real differences · 4 level
GRAB EM Field Synth versus Pocket Lofi: the parameters behind the verdict, then further details
ParameterGRAB EM Field SynthPocket Lofi
Price$3.99Free — better
Rating—1.0 (1 ratings) — better
Positive reviews100.0% of reviews — better0.0% of reviews
Number of ratings—1 — better
Update frequencyDaily — betterEvery 5 weeks
AdsNo — betterYes
In-app purchasesNo — betterYes
MonetizationPaidFreemium — better
DevicesiPhoneiPhone
Requires iOS17.016.0 — better
Further details — not scored
Size2 MB155 MB
Age rating4+4+
DeveloperHiroya TanakaAnum Mian

Customer experience

GRAB EM Field Synth

Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Pocket Lofi

All ratings1 ratings
Positive0.0%
Neutral0.0%
Negative100.0%
Written reviews1 reviews
Positive0.0%
Neutral0.0%
Negative100.0%

In-app purchases

None

GRAB EM Field Synth

No in-app purchases

2 purchases

Pocket Lofi

Subscriptions1
  • Monthly Subscription$2.991 Month
One-time1
  • Lofi Lifetime$24.99

Questions

Is GRAB EM Field Synth free?
GRAB EM Field Synth costs $3.99, with no in-app purchases.
Is Pocket Lofi free?
Pocket Lofi is free to download, with in-app purchases available.
Do GRAB EM Field Synth or Pocket Lofi have ads?
Pocket Lofi shows ads; GRAB EM Field Synth does not.
Which is updated more often, GRAB EM Field Synth or Pocket Lofi?
GRAB EM Field Synth ships an update daily, and Pocket Lofi every 5 weeks. Most recently, GRAB EM Field Synth was updated on October 31, 2026 and Pocket Lofi on October 31, 2026.

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