The popular Blue Iris software for surveillance camera is being upgraded to v5 on 1 June. The developer has said the purchasing the new full version will cost more than the existing full v4 version (US$69.95, or US $50 using the IPCam link posted in the comment below). But for existing users you can upgrade to v5 by purchasing extended support at US$29.95 https://blueirissoftware.com/support/
Just a friendly reminder for current users.
Better than MileStone's XProtect? Essential+ gives you 8 Free camera licenses,and their support for the free version is exceptional.