Comparison

D vs Allergy Diary

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

Head to head
About

D

Features
Read full description

D-SYNC ECU is the ultimate calibration platform for Mercedes-AMG and Mercedes-Benz owners who demand more from their vehicles. Unlock your car's full potential — D-SYNC delivers a seamless, wireless tuning experience straight from your phone. No laptop, no cables, no dealer. SUPPORTED ENGINES • M177 4.0L V8 BiTurbo — C63 S, E63 S, S63, GT 63 S, GLE 63 S, GLC 63 S, and more • M178 4.0L V8 BiTurbo — AMG GT / GT S / GT C / GT R / Black Series • M276 3.0L V6 BiTurbo — C43, E43, E450, GLC43, GLE43, S400, and more • M157 / M278 5.5L & 4.7L V8 BiTurbo — S63, CLS63, GLE63, GLS63, ML63, E63, and more • M133 2.0L Turbo — CLA45, A45, GLA45 (Gen 1 / 1.5) • M256 3.0L Turbo inline-six — E53, CLS53, GT53, GLE53 and 450 models PLUS TRANSMISSION TUNING AND CPC TUNING • 9G-TRONIC (VGS-NAG3) — write calibrations directly to the 9-speed transmission controller • CPC NG - write customized calibrations to a replaced CPC NG module. Compatible control units: Bosch MED17.7.5 Ā· MED17.7 V6LA Ā· MED40AMG Ā· MED17.7 (M157/M278) Ā· Bosch MG1 (M256) Ā· VGS-NAG3 (9G) Ā· CPCNG HIGH-SPEED DATA LOGGING • Ready-made logging presets per engine, plus build-your-own profiles (up to 20 channels) • Boost, intake temps, knock, AFR/lambda, timing and 70+ parameters in real time • Auto-records your pull and saves it as a CSV tagged by VIN, date and time • Powerful viewer — multi-channel overlay, drag-to-read cursor, time-axis zoom and stacked view • One-tap cloud sharing so your tuner can refine the calibration LIVE HUD Turn your phone into a full-screen instrument cluster while you log. Big, glanceable gauges with per-cylinder knock and misfire, camshaft timing, and automatic over-limit alerts — portrait or landscape, with dedicated layouts per engine. Display only: it never touches your recording. EXHAUST POP & BANG TUNER (AMG only) Dial in custom exhaust pops & bangs on OTS tunes — presets plus advanced control, applied at flash. DTC DEACTIVATION Deactivate diagnostic trouble codes across all firmware versions, applied at flash. VEHICLE CODING (beta) Activate hidden features and adjust factory coding — including W205 brake/model coding and AMG 63 exhaust-flap coding. Supported coding is listed at d-syncworks.com. CONTROL-UNIT REPLACEMENT & CLONING (beta) Clone-write the next-generation Common Powertrain Controller (CPC NG), including control-unit replacement. AIRMATIC SUSPENSION CONTROL (beta) Dial in ride height on supported AIRMATIC chassis — AMG GLE/GLS (W167), S-Class (W222) and E-Class (W213). Save your favorite stances and recall them in a tap. ON-BOARD DIAGNOSTICS Read and clear fault codes with plain-language descriptions, right from the app. BUILT FOR AMG Every detail is engineered around the Mercedes platform — automatic ECU identification, per-vehicle configuration, and a tuner ecosystem that speaks your language. WHAT YOU NEED • D-SYNC D1 Bridge — WiFi hardware adapter (sold separately at d-syncworks.com) • A supported Mercedes-AMG / Mercedes-Benz listed above • A D-SYNC account and license Questions or support? Visit d-syncworks.com Note: M256 flashing requires a one-time bench unlock before wireless flashing is available. ** This racing product is for competition, closed-course use only. *** Use of this software may void portions of your vehicle's factory warranty. Some items may not be legal for on-highway use. D-SYNC makes no guarantees as to the legality of any parts used on highway vehicles and accepts no responsibility for compliance with your vehicle's factory warranty.

About

Allergy Diary

Features
Read full description

Record the severity of sneezing, runny nose, nasal congestion, itchy eyes, cough and skin rash, with notes. Edit daily entries and review symptom intensity on the calendar. The app interface is in Korean. Review trends, symptom distributions and weekday patterns from your entries. Copy a summary to discuss with a clinician. These statistics summarize self-reported records and do not diagnose an allergen or a condition. Symptoms vary between people; consult a doctor or pharmacist. The app does not recommend medication timing or doses. When pollen data is available, the app displays Korea Meteorological Administration predictions for a representative location in the selected Korean region, with the target date. These are not measurements or assessments of your personal allergy risk. Oak and pine data cover April through June; weed data covers August through October. Mugwort, dates outside the supported season, missing data and failed connections are shown as unverified, without a risk grade. Symptom recording remains available when pollen data cannot be provided. Enable reminders and allow device notification permission to receive a diary reminder at your chosen time. Pollen reminders ask you to check data in the app; they do not predict the next day's risk. No account is required. Record symptoms offline and keep entries on your device. The app is free to use, with no ads or tracking permission prompts. The iOS Home Screen widget shows whether you recorded today and your consecutive recording days.

Screenshots

D4 screens
Allergy Diary4 screens

Verdict

The call

The clearest difference is update cadence: Allergy Diary at daily against D's every 5 days. Allergy Diary also leads on iOS requirement (13.0 vs 15.0). On price, ads, in-app purchases and device support there is nothing between them.

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

CostPrice Ā· In-app purchases Ā· Ads Ā· Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

D ships an update every 5 days, Allergy Diary daily. Both last shipped on November 5, 2026.

Scorecard2 real differences Ā· 4 level
D versus Allergy Diary: the parameters behind the verdict, then further details
ParameterDAllergy Diary
PriceFreeFree
Update frequencyEvery 5 daysDaily — better
AdsNoNo
In-app purchasesNoNo
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.013.0 — better
Further details — not scored
Size43 MB35 MB
Age rating4+4+
DeveloperLUN LIUHeungYeol Kim

In-app purchases

None

D

No in-app purchases

None

Allergy Diary

No in-app purchases

Questions

Is D free?
D is free to download, with no in-app purchases.
Is Allergy Diary free?
Allergy Diary is free to download, with no in-app purchases.
Do D or Allergy Diary have ads?
Neither D nor Allergy Diary shows ads.
Which is updated more often, D or Allergy Diary?
D ships an update every 5 days, and Allergy Diary daily. Most recently, D was updated on November 5, 2026 and Allergy Diary on November 5, 2026.

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