I use a simple housing for a raspberry pi, which uses suction cups to stick to any window pointing at trees or any vegetation. The schematics in FreeCAD format can be found here. I also provide DXF drawings which can be used in a laser cutter or CNC machine. For those with a 3D printer an SLT is provided as well however but I'm not sure about the strength of the design (both the SLT and DXF files are rather outdated, so for the latest design use the FreeCAD files). Below I show the original version without any buttons or indicator LED. These functions have been added in later iterations.
I would say that from a hardware point of view the project is finished! I did consider some alternative setups but they all lead to either increasing cost, complexity and / or degraded data (moving camera lenses would cause drift which is a major issue in post processing).
The current sofware can be found on my bitbucket PhenoPi page. The code available currently covers an upload script which triggers the camera, a script which pulls additional localized weather data, an installation script for the former and a script to install a real time clock if necessary (still ugly, damn systemd).
Currently the majority of the work is software based, trying to streamline the install to make it as painless as possible. A complete hands off install will not be possible, especially when one wants a wireless setup, so it will always remain sort of a DIY project I fear. The current software has been running for weeks at my parent's place, capturing the onset of spring greenup nicely (see attached figure and progress report)!
Post processing software is already in place as this is an integral part of the PhenoCam project. All software is freely available online and can be found here.