I have been using Minvo for this purpose. But, it is too slow when i just want to do captioning.
this product is way better. Fast caption editing possibility. Quick rendering, Download is little slower than expected when it is rendered.
The only negative i found at the moment is about the featrues which seems weird in today's world. Give 75 mins per month in first plan. Let users decide, whether they want to upload 3 mins video, 1 minute video, 5 min or 15 mins video and generate captions.
And 500 mb file size limit is too little When videos are 4k or in good clarity with good bit rate. In such cases, you can keep a condition that it will be retained in the account for lesser number of days. (To reduce server load)

Overall, am super happy using this app.
I think, developer should think about better pricing strategy to not push away users who need flexibility and should not be bound by random decisions about 25 videos and max 3 mins each. 75 to 90 mins (irrespective of mins per video) would be a better plan to experiment the product for those users who will be just trying out the product for the first time.