Professional AI Subtitle Translation

SubEnvoy is your personal AI media bridge, designed to break language barriers for all your local video content. It combines high-accuracy on-device AI transcription (offline) with professional-grade cloud translation. To protect your privacy, video files are processed entirely on your device and never leave it; only the extracted subtitle text is uploaded to the cloud for translation.

Yes, SubEnvoy offers a free trial and the on-device transcription features are completely free. Since AI translation utilizes costly large language models, it is paid via a "Points System." 1 USD (100 pts) translates to approximately 5 hours of video in Standard mode (about 15 pts for a standard TV episode, depending on subtitle volume). Standard mode balances cost and quality for daily viewing, while Advanced mode uses top-tier models for professional-grade context and quality, consuming about 3x more points.

Just open your video file or import external subtitles in SubEnvoy. If the video contains built-in subtitle tracks, you can switch between them in the interface. The system automatically extracts the active subtitle content, which you can then submit to the server for AI translation. It usually takes just a few minutes, after which you can save or export the translated subtitles.

You can use the built-in "Local Transcription" feature. The system uses the advanced Whisper AI model to turn video speech into text subtitles in real-time. This process runs entirely offline on your device, leveraging Apple's Neural Engine for hardware acceleration. Once finished, you can export the subtitles or submit them to the server for further AI translation.

The first time you open transcription on iOS, Core ML does a one-time device-specific specialize / prewarm step for the local model. That is why the first run takes much longer. A new device usually needs around 10 minutes, and older devices can take longer. After that, later runs are much faster. If speed matters most, the Mac desktop version is usually the better choice because it can use the hardware with fewer battery, memory, and CPU limits.

Local transcription runs entirely offline. Translation only sends text segments to the cloud; your media files never leave your computer.

SubEnvoy has two types of points: Subscription Points reset at the end of each billing cycle and do not roll over. Point Pack balances are protected differently—subscribers (any tier) enjoy permanent validity; non-subscribers receive 365-day asset protection; if there is no active subscription and no account activity for 365 consecutive days, the balance will be forfeited to clean up inactive accounts. Any renewal or new purchase resets the protection countdown.

This usually happens when the same Apple ID had previously subscribed on an old account, the subscription later expired, and you then signed in to a new account and purchased again. Due to Apple in-app purchase rules, the system may still attach the new subscription to the old account previously linked to that Apple ID, so the app may show a purchase failure first and then, after refresh, show that the entitlement was attached to the old account. This does not mean you were charged twice or that your entitlement was lost. It means the subscription was automatically linked back to the old account. In this case, you can use the in-app entitlement transfer feature, available once every 90 days, to move the purchase to your current account, or simply sign in to the old account and continue using it.