Secondary display for subtitles
Problem
Subtitle users (deaf/hard-of-hearing, audio processing disorder, language learners) are forced to watch content with captions covering the action: subtitles sit on top of the video, overlap with burned-in subtitles, and obscure faces and sports. A r/Doesthisexist post asking for a small soundbar-style screen under the TV that displays subtitles separately got 112 upvotes and 16 comments, with many users describing the exact same frustration.
Opportunity
A compact HDMI/USB secondary display device (or app for a spare phone/tablet) that reads SRT files or captures CC streams and renders subtitles on a dedicated strip below the TV, keeping the main picture clean.
Market analysis
The pain is real and well-validated (112 upvotes, and Caption Companion proves a market for companion caption displays), but a true 'subtitle soundbar' hits two walls: HDCP encrypts HDMI caption streams and streaming apps expose captions nowhere external. The solo-builder wedge is a spare-tablet app, which covers only local media files.
Market · Deaf/HoH viewers, people with audio processing disorder, and language learners; accessibility niche with proven engagement and at least one dedicated hardware product already shipping.
Pricing · Dedicated captioning devices sell as one-time hardware (8-inch caption tablets); consumer accessibility gadgets typically land in the low hundreds of dollars, while a companion app would be a $3-8 one-time or freemium purchase.
Pros
- + Genuinely felt pain, echoed across many commenters in the source thread.
- + Spare-phone/tablet MVP needs no hardware, no backend, just an SRT player.
- + Accessibility communities are vocal and reachable for distribution.
Cons
- − HDCP and streaming DRM make capturing the TV's own caption stream effectively impossible for a third-party device.
- − A hardware strip display requires capital, molding and certification a solo builder rarely has.
- − TV vendors could absorb this natively (caption repositioning/external display) at any time.
Source
r/Doesthisexist (Reddit)
The hard part is not the display, it is getting the caption signal. HDMI is HDCP-encrypted and no streaming app exposes its caption track to external devices, which is why the product that actually shipped in this space (Caption Companion) quietly sidesteps the problem: it re-transcribes room audio with speech-to-text instead of reading the TV’s captions. That is the real insight here — a winning version is a listener, not a pass-through, and a spare tablet running on-device ASR synced to the TV audio delivers ~90% of the value with zero hardware. Latency and accuracy in a noisy living room then become the actual product, and that is a software problem a solo builder can iterate on weekly rather than a hardware bet they can only make once.