Comparison

Battery vs Rootbly

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

Head to head
About

Battery

Explore the fundamental principles of electrochemical cells and their conversion of chemical to electrical energy. Understand the distinction between disposable primary batteries and rechargeable secondary batteries, and their diverse applications.

Highlights
  • Electrochemical cell principles
  • Chemical to electrical energy conversion
  • Primary (disposable) batteries
  • Secondary (rechargeable) batteries
  • Applications of batteries
Features
Read full description

An electrical battery is one or more electrochemical cells that convert stored chemical energy into electrical energy. Since the invention of the first battery (or "voltaic pile") in 1800 by Alessandro Volta, batteries have become a common power source for many household and industrial applications. According to a 2005 estimate, the worldwide battery industry generates US$48 billion in sales each year, with 6% annual growth. There are two types of batteries: primary batteries (disposable batteries), which are designed to be used once and discarded, and secondary batteries (rechargeable batteries), which are designed to be recharged and used multiple times. Miniature cells are used to power devices such as hearing aids and wristwatches; larger batteries provide standby power for telephone exchanges or computer data centers.

About

Rootbly

Watch foreign YouTube videos with AI-generated translated subtitles in real-time. Paste a URL to get instant subtitles in your preferred language, with options to adjust sync, size, and view original text.

Highlights
  • AI subtitle translation
  • 15 languages supported
  • Real-time subtitle display
  • Subtitle sync adjustment
  • Customizable subtitle size
  • YouTube search and browsing
  • Job progress tracking
Features
Read full description

Watch foreign YouTube videos with translated subtitles. RootblySub auto-translates YouTube subtitles into your language. Just paste a URL, and AI generates subtitles you can watch instantly in our built-in player. ◆ CORE FEATURES • AI Subtitle Translation — 15 languages including English, Korean, Japanese, Chinese, Spanish, French, and more • Built-in Video Player — Translated subtitles displayed in real-time over the video • Subtitle Sync Control — Manual offset adjustment within ±5 seconds • Subtitle Size Settings — Small/Medium/Large presets with fine-grained control • Original Text Toggle — View translation alongside or without the original ◆ YOUTUBE BROWSING • YouTube Search — Find videos directly within the app • Channel Browser — Explore videos, Shorts, playlists, and live streams • Channel Favorites — Save channels you watch frequently • Clipboard Detection — Auto-detect copied YouTube URLs ◆ TRANSLATION JOB MANAGEMENT • Real-time Progress — Track each stage: downloading → transcribing → translating • Push Notifications — Get notified the moment translation is complete • Job History — Manage all your translation requests in one place ◆ CONVENIENCE • Sign in with Google / Apple or use Guest mode • YouTube Premium integration for ad-free viewing • Korean & English UI • Fullscreen landscape mode Enjoy YouTube content from around the world — no language barriers. --- 외국어 유튜브 영상, 이제 자막 번역으로 쉽게 보세요. RootblySub은 YouTube 영상의 자막을 원하는 언어로 자동 번역해주는 앱입니다. URL을 붙여넣기만 하면 AI가 자막을 생성하고, 내장 플레이어에서 바로 시청할 수 있습니다. ◆ 핵심 기능 • AI 자막 번역 — 한국어, 영어, 일본어, 중국어 등 15개 언어 지원 • 내장 비디오 플레이어 — 번역 자막이 영상 위에 실시간 표시 • 자막 싱크 조절 — ±5초 범위에서 수동 오프셋 조절 가능 • 자막 크기 설정 — 소/중/대 프리셋 및 세밀한 크기 조절 • 원문 자막 토글 — 번역과 원문을 함께 또는 따로 보기 ◆ 유튜브 탐색 • YouTube 검색 — 앱 안에서 바로 영상 검색 • 채널 브라우저 — 영상, Shorts, 재생목록, 라이브 탐색 • 채널 즐겨찾기 — 자주 보는 채널을 저장 • 클립보드 자동 감지 — 복사한 YouTube URL을 자동 인식 ◆ 번역 작업 관리 • 실시간 진행률 — 다운로드 → 전사 → 번역 단계별 상태 표시 • 푸시 알림 — 번역 완료 시 즉시 알림 • 작업 이력 — 모든 번역 요청 목록 관리 ◆ 편의 기능 • Google / Apple 로그인 또는 게스트 모드 • YouTube Premium 연동으로 광고 없이 시청 • 한국어 / 영어 UI 지원 • 전체화면 가로 모드 지원 언어 장벽 없이 전 세계 유튜브 콘텐츠를 즐기세요.

Screenshots

Battery1 screens
Rootbly4 screens

Verdict

The call

The clearest difference is rating: Rootbly at 4.0 against Battery's 3.5. Rootbly also leads on in-app purchases (none vs 1) and update cadence (fortnightly vs monthly). Battery's advantage is ratings volume (13 vs 1) and iOS requirement (6.0 vs 16.4). On price, ads and device support 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

Both are free to download. Battery sells 1 one-off in-app purchase. Rootbly asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Rootbly holds the better App Store score, 4.0 against 3.5. That said, the two scores are not equally well evidenced: Battery has 13 ratings behind it against 1, so its average is the more settled of the two.

UpkeepUpdate frequency

Battery ships an update monthly, Rootbly fortnightly. The most recent releases landed on October 8, 2026 and October 14, 2026 respectively.

Scorecard6 real differences · 4 level
Battery versus Rootbly: the parameters behind the verdict, then further details
ParameterBatteryRootbly
PriceFreeFree
Rating3.5 (13 ratings)4.0 (1 ratings) — better
Positive reviews29.4% of reviews—
Number of ratings13 — better1
Update frequencyMonthlyFortnightly — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchasesFree — better
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS6.0 — better16.4
Further details — not scored
Size4 MB41 MB
Age rating4+4+
DeveloperOrgajja Co LtdByeongsu KIM

Customer experience

Battery

All ratings13 ratings
Positive61.5%
Neutral7.7%
Negative30.8%
Written reviews119 reviews
Positive29.4%
Neutral10.1%
Negative60.5%

Rootbly

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

Bugs and requests

Battery

Reported bugs

20 issues
  • Crashes on opening
  • Opens ads and redirects
  • Lagging out device
  • Cannot use all functions without download
  • Doesn't open
Show 15 more
  • Black screen then crash
  • App crashes immediately after update
  • Force closes
  • Battery percentage inaccurate
  • App doesn't work
  • Keeps flashing back to home screen
  • Latest update broke the app
  • Advertisements prevent app from working
  • App crashes my iPod
  • App crashes whenever I want to use it
  • App keeps shutting off
  • Doesn't load for many users
  • App doesn't start up
  • Keeps booting back to main screen
  • Never works right

Requested features

8 requests
  • Remove ads
  • Upgrade option to remove ads
  • Add more functions
  • Remove slot machine game prompt
  • Fix crashing issues
Show 3 more
  • Update app for stability
  • Add settings for personalization
  • Explain calendar function

Rootbly

Not enough reviews yet to summarise bugs or requests.

In-app purchases

1 purchases

Battery

One-time1
  • Upgrade$0.99
None

Rootbly

No in-app purchases

Questions

Is Battery free?
Battery is free to download, with in-app purchases available.
Is Rootbly free?
Rootbly is free to download, with no in-app purchases.
Which has better reviews, Battery or Rootbly?
Rootbly is rated higher. Battery averages 3.5 out of 5 from 13 ratings, while Rootbly averages 4.0 from 1 ratings.
Do Battery or Rootbly have ads?
Neither Battery nor Rootbly shows ads.
Which is updated more often, Battery or Rootbly?
Battery ships an update monthly, and Rootbly fortnightly. Most recently, Battery was updated on October 8, 2026 and Rootbly on October 14, 2026.

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