simple and straight forward

This app is easy to set up and easy to use. Do not expect something fancy.
Assigning static IP addresses to your cameras is advisable, so the app cannot loose them in case they change.
input IP address, user name and pw, and off it takes. Individual windows open for each camera, which you can move around as you please.
I use two monitors connected to a mac mini, and witht that setup I keep an eye on two entrances and hall ways with d-links 930L/932L, again, simple and unspectacular, but it works.
Really do not see the point of the great many one-star reviewers.

angelico6 about D-Link++ Viewer