This is overkill (rampant HA OCD)....
but I use and like Blue Iris, Sighthound (formerly known as VitaminD), and Synology's Surveillance Station software for camera motion detection sensing and recording. All three software programs trigger recording and/or alerts (via email, texts, or cell phone notifications) under a variety of circumstances. I do not record 24/7 but trigger recording (and notification) based on events.
I like the motion analyics in Sighthound and the fact that I can create a rule ("People on Front Porch"), get notices of any violation of that rule, and yet also have a recording of any object in the camera's field of view retained for about 2 days even if not covered by the rule (which, for examples, lets me go back and see cars in the street or people on the sideway out front). There is also an iPhone app.
I like the customizaation Blue Iris offers, and I love the BI iPhone app. It is my preferred remote camera app. Blue Iris is highly confirgurable as to when and what it does (I'm still learning) and I use the geolocation feature of the app to customize recording/notice features keyed to whether I am at home or not.
I don't have a standalone DVR, but recently got a Synology Diskstation (mainly for NAS needs) and am using the Surveillance Station app on the Synology DS for DVR purposes. I like that that the Synology generally seems to give me longer recordings when triggered, but the setup is a lot more complicated and fussy than the other two products.
My suggestion is that you look at some of the other posts on the forum using prodcut names as search terms or general inquiries, and see what others here have done or tried. That will give you a sense of what is available, and you can then download trials of whatever seems to meet your needs and desires.