I don't know if any camera system that doesn't require a subscription for viewing past events. My Ring doorbell requires it, as does pretty much all other brands. I have an inexpensive camera pointing at an outside parking pad at my home. While it allows me real time video playback, I only get images if it alerts, no video playback. Since I don't pay any subscription fee, I wouldn't expect to have past video playback.
But I do have an SD card in that cheap camera, so I can pull it out and view the video that it saved. The same is true with the Roku camera. You can put an SD card in the camera and remove it to play any recorded video back. That doesn't require a subscription.
At this time I haven't subscribed to the service for my Roku cameras (I have three of them). I haven't decided if it's worth it to me yet, but I have a feeling that I will add it in the future. While the live camera feed is nice to have, there's value in having historical playback without needing to pull the SD card.
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