Comparison

Build SRT vs Caption AI

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

Head to head
About

Build SRT

This utility converts spoken audio from videos into standard SRT subtitle files. It supports importing videos from your device and offers efficient sound extraction for subtitle generation. The generated SRT files are universally compatible and easily shareable.

Highlights
  • Speech-to-text transcription
  • Import videos from Photos and Files
  • Extract audio for SRT generation
  • Universal SRT file format
  • Share SRT files easily
Read full description

Build SRT leverages Apple’s built-in speech recognition framework to convert spoken audio into text. You can use the system’s native speech-to-text functionality to experience its transcription accuracy firsthand. To complement the limitations of the built-in recognizer, the app also supports manual import of natural language text, offering greater flexibility in subtitle creation. The app generates subtitle files in standard SRT format, but it does not produce new video files with embedded subtitles. The "Build SRT" App can efficiently extract the voice in the video and convert these sounds into subtitle SRT files. The generated subtitle SRT file is a universal subtitle file format, so that you can use the subtitle SRT file widely. Features: • It is very convenient to import videos from the system "Photos" and "Files" • Import videos at the same time and view subtitles according to the video at a glance • Efficiently and quickly extract the sound in the video and convert it into an SRT file • SRT files can be quickly shared on other devices.Support sharing, copying, spacing and forwarding on Apple system to facilitate exporting SRT files for modification and use. • SRT files are a universal subtitle file format and can be used widely. Support: If you have any suggestions and comments, please do not hesitate to contact the developer: Email: hanmingjie@gmail.com WeChat: MingJie-Han

About

Caption AI

Features
Read full description

Add automatic subtitles to your videos so viewers can follow what you say, even with the sound off. Translate your subtitles and customize their look with Caption AI. Made for vlogs, tutorials, and everyday stories, Caption AI brings subtitle creation and useful video tools into one app. AUTOMATIC VIDEO SUBTITLES Turn speech in your video into on-screen text and reduce manual typing. Generate subtitles for your footage, then review the result before sharing. TRANSLATION AND BILINGUAL SUBTITLES Translate subtitles into supported languages and display the original alongside the translation. Customize the style of each language separately to help viewers tell them apart. Available recognition and translation languages are shown in the app. YOUR SUBTITLES, YOUR STYLE Choose fonts, adjust text size and color, and customize layout and alignment. Match the subtitles to your video and keep the words easy to read. BASIC VIDEO EDITING Trim and cut footage, change playback speed, and adjust brightness, contrast, and saturation as part of your subtitle workflow. A TELEPROMPTER FOR YOUR SCRIPT Read scrolling text with adjustable speed, font size, and colors. Use it to support presentations, vlogs, and other scripted content. MORE TOOLS FOR VIDEO CREATION - Split-screen video: combine two clips side by side or vertically, with adjustable positioning and proportions. - Video compression: choose high, medium, or low quality to balance file size and image quality. - Chat videos: create fictional one-to-one or group conversations for storytelling and content demonstrations. - Video assets: browse, filter, and download clips to use in your projects. START WITH A VIDEO Choose your footage, generate and translate subtitles, adjust their appearance, and export your captioned video. PREMIUM FEATURES Automatic speech recognition, subtitle translation, captioned-video export, and ad removal are premium features. Check the in-app purchase screen for available plans, prices, feature access, and any usage limits. Auto-renewable subscriptions renew unless canceled. You can manage subscriptions in your App Store account settings. Check the purchase screen for the terms of each option. Contact: nicekeep@126.com Privacy Policy https://www.freeprivacypolicy.com/live/39e5616d-405f-4dd4-a783-77fa720f49b2 EULA https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Terms & Conditions https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ ---------------------------------------------------------------------- 1. VIP Membership VIP membership includes Weekly, Monthly, Yearly, and Lifetime plans. With a Premium Membership, you can enjoy the following features: • Remove all ads • Automatically recognize speech in videos • Translate subtitles into multiple languages • Export videos with subtitles 2. Subscription Plans The subscription plans provide access to ad-free experience, automatic speech recognition, subtitle translation, and exporting subtitle videos. This app offers the following subscription options: • $2.49 per week • $3.99 per month • $13.99 per year • $55.99 Lifetime purchase 3. Subscription Payment and Auto-Renewal Payment will be charged to your App Store account when you confirm the purchase. Subscriptions will automatically renew unless auto-renewal is turned off at least 24 hours before the end of the current subscription period. You can manage or turn off auto-renewal at any time in your App Store account settings after purchase.

Screenshots

Build SRT4 screens
Caption AI4 screens

Verdict

The call

The clearest difference is price: Caption AI at Free against Build SRT's $2.99. Build SRT's advantage is in-app purchases (none vs 4) and device support (3 vs 1). On update cadence, ads 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

Caption AI is free to download; Build SRT costs $2.99 up front. Caption AI sells 4 in-app purchases, starting at $2.99 per 7 days. Build SRT asks for nothing beyond the download.

UpkeepUpdate frequency

Build SRT ships an update every 5 weeks, Caption AI monthly. The most recent releases landed on August 14, 2026 and September 26, 2026 respectively.

Scorecard3 real differences · 7 level
Build SRT versus Caption AI: the parameters behind the verdict, then further details
ParameterBuild SRTCaption AI
Price$2.99Free — better
Rating5.0 (1 ratings) — better—
Positive reviews0.0% of reviews—
Number of ratings1 — better—
Update frequencyEvery 5 weeksMonthly — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationPaid—
DevicesiPhone, iPad, Mac — betteriPhone
Requires iOS17.616.0 — better
Further details — not scored
Size25 MB48 MB
Age rating4+4+
Developer韩 明洁Beijing Xingnian Trading Department (Individually Owned Business)

In-app purchases

None

Build SRT

No in-app purchases

4 purchases

Caption AI

Subscriptions3
  • Weekly$2.997 Days
  • Monthly$3.991 Month
  • Annual$14.991 Year
One-time1
  • Lifetime$59.99

Questions

Is Build SRT free?
Build SRT costs $2.99, with no in-app purchases.
Is Caption AI free?
Caption AI is free to download, with in-app purchases available.
Do Build SRT or Caption AI have ads?
Neither Build SRT nor Caption AI shows ads.
Which is updated more often, Build SRT or Caption AI?
Build SRT ships an update every 5 weeks, and Caption AI monthly. Most recently, Build SRT was updated on August 14, 2026 and Caption AI on September 26, 2026.

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