Built and run
end to end
EltaCrew (elta) is an Android, backend and web developer who takes products from idea to launch — planning, code, design, release and operations. Below are 24 published Android apps and 6 web services, spanning pet care, food safety, government benefits, TV remotes and productivity tools.
Everything here is live on Google Play or ONE store, or usable straight from your browser. Tap a card to open it.
Published Apps
All apps are live on Google Play (PillDex is Korea-only, also on ONE store). Most work without sign-up and keep your data on-device.
Dog Tick Finder
Find ticks in dog fur using camera color inversion and on-device AI.
View on Google Play ↗PawLog
Daily walk, meal, and health log for dogs with early-warning alerts.
View on Google Play ↗LinkDrawer
Save links from any app with one share tap, then find them again by tag, folder or full-text search. Imports browser bookmarks and backs up to a single file.
View on Google Play ↗MdViewer
Markdown viewer and editor rendering tables, code, and math from your folders.
View on Google Play ↗FoodSafety
Track expiry dates for what is in your fridge and get a push, even with the app closed, when an official food recall matches your items. Add food by icon, receipt photo or barcode.
View on Google Play ↗ScanQ
Turn a photo into a clean scanned PDF. QR/barcode scan, doc scan, OCR, and QR generator.
View on Google Play ↗Phonest
Yesterday's phone use as a witty morning card. 100% on-device.
View on Google Play ↗BenefitHub
Government and youth benefits matched to you, with D-day alerts.
View on Google Play ↗TapFlare
A one-thumb neon tapper — the whole world runs the same daily course.
View on Google Play ↗AdDeck
AdMob and AdSense revenue combined in one dashboard. Read-only, zero server.
View on Google Play ↗SunGlow
Golden hour, sunrise, sunset, and moon times on your home screen. 100% on-device astronomy.
View on Google Play ↗Lotto Daebak
AI number picks from draw stats, birthday fortune numbers, and a jackpot-store map.
View on Google Play ↗MeasureKit
Compass, decibel meter, bubble level, ruler, magnifier, protractor, inclinometer, vibration and lux meter — nine sensor tools in one app.
View on Google Play ↗HabitDeck
A habit tracker for water, sleep, workouts, mood, weight and quitting — one tap a day, with reminders, calendar, stats, lock and backup.
View on Google Play ↗ExamDay
Exam countdown on a home screen widget, with 21 presets, photo backgrounds, a per-subject study timer and spaced-review reminders.
View on Google Play ↗Sitedex App
The hand-picked website directory as an Android app — browse by category, save sites, search offline, in five languages.
View on Google Play ↗FixCode
Look up appliance error codes by brand — cause, urgency and DIY fixes on one screen. The code database ships inside the app, so search works offline.
View on Google Play ↗Genie TV Remote
A remote for Genie TV (olleh TV) set-top boxes and Android TV over IR, Bluetooth or Wi-Fi — works on phones without an IR blaster.
View on Google Play ↗B tv Remote
A remote for B tv set-top boxes and Android TV over IR, Bluetooth or Wi-Fi — works on phones without an IR blaster.
View on Google Play ↗U+tv Remote
A remote for U+tv set-top boxes and Android TV over IR, Bluetooth or Wi-Fi — works on phones without an IR blaster.
View on Google Play ↗Skylife Remote
A remote for Skylife and QookTV set-top boxes and Android TV over IR, Bluetooth or Wi-Fi — works on phones without an IR blaster.
View on Google Play ↗TV Remote
One free remote app for Samsung, LG, Sony, Android TV, Google TV and Chromecast. It finds the TV on your Wi-Fi by itself, mirrors your phone screen and sends photos and videos to the TV.
View on Google Play ↗TV Remote Receiver
The TV-side companion to the TV Remote phone app, for Android TV and Google TV. Keep it open, tap Mirror in TV Remote on your phone, and your phone screen plays on the TV over the same Wi-Fi, with sound. No sign-up, no ads.
View on Google Play ↗PillDex
Identify a pill by its imprint or a photo, check drug interactions, set dose reminders and find open pharmacies. Built on Korean MFDS open data; on Google Play and ONE store (Korea only).
View on Google Play ↗Web Services
Tools and information services you can use right in the browser — no install needed.
Sitedex
A curated, multilingual directory of useful websites — 800+ sites across 9 categories, with search and open submissions.
Open Sitedex →Benefits Web
Government and public benefits — welfare, youth, startup, jobs — sorted by closing date, with full-text search.
Open Benefits Web →Web SSH
A browser-based SSH client with a real xterm terminal and SFTP — no install, credentials never stored.
Open Web SSH →FixCode
Look up what the error code on your washer, air conditioner or boiler means. 6,086 codes from 202 brands, organised by manufacturer and product type, each with the likely cause and what to check.
Look up an error code →Video Merger
Merge multiple videos into one right in the browser — nothing uploaded, mixed resolutions handled automatically.
Open Video Merger →Markdown ↔ HTML Converter
Convert Markdown and HTML both ways right in the browser. Drop several md, html and image files at once and export a single self-contained HTML with tables, syntax highlighting, diagrams and math preserved — or turn HTML back into Markdown, including from a web address. Nothing is ever uploaded.
Open the converter →Field notes
Numbers I measured and problems I hit while running 24 apps and 6 web services: ad revenue, Play policy and review, store search, implementation traps, web deployment.
Why our lottery ticket QR scanner showed zero successes: a path you don't log looks like a failure
In our lottery app's weekly report, 19 people had opened the QR screen and GA4 showed zero successful scans. The scanner wasn't broken. The path that real ticket QR codes took had no logging at all. How we found the measurement gap, what four similar apps do, why we switched to the bundled scanning engine, and the numbers one week after the fix.
Read →Tapping the logo in the map's corner crashed the app: Naver Map SDK and the AppCompat theme
Four "You need to use a Theme.AppCompat theme" crashes showed up in Crashlytics for our lottery store map app. They came not from users but from the Play pre-launch report's test robot tapping the NAVER logo in the bottom-left corner of the map. The cause, a fix that wraps only the map instead of changing the whole app theme, and a second problem that appeared in dark mode.
Read →Requesting ads before the SDK finishes initializing: why the same crash came back three times after we added a guard
After we first fixed the "MobileAds.initialize must be called" crash in our live apps, the same crash came back three more times in different shapes. We had a guard that waited for initialization to finish, but a flag set at the start, a flag set on consent alone, and new ad slots that skipped the guard all left gaps. The cause of each case and the results of checking all 23 apps.
Read →A crash from one line of image downsampling: inSampleSize starts at 0
To save memory, we changed the document thumbnails in our QR scanner app to load downsampled. In the next version, the app closed every time the document list opened. The cause was that BitmapFactory.Options.inSampleSize defaults to 0. The code we changed, the crash data, the fix, and how we checked for the same mistake elsewhere.
Read →The crashes Crashlytics didn't show: it only sees the builds you added it to
Three days after adding Firebase Crashlytics to 21 apps, we found a user-facing crash in Play Console first. Crashlytics only reports from builds that include the SDK, and crashes from older versions still on users' phones pile up only in Play vitals. Results from checking all 21 apps, and the order we check in now.
Read →The day a sync deleted 8,802 stores: one renamed API field and a 100-row list
In our lottery retailer map app, a sync turned every store name into "Unknown" and wiped the 8,802 stores bundled with the app. Three causes — a renamed field in a public data API, a sync that deleted rows based on only the first 100 results, and a geocoder reading keys that do not exist — and how each was fixed.
Read →About EltaCrew
EltaCrew is the studio of Android developer elta. Across payment terminals, interactive mirrors, pet care and IoT systems, elta has planned, built and operated products end to end. The apps and web services above are all live for real users, built with public-data APIs, on-device AI and browser-based tooling.