TunerStudio MS
TunerStudio MS is the de facto standard for tuning MegaSquirt ECU's. It offers 3D mapping, auto-tuning, custom dashboards and other advanced features. It's written mostly in Java, so it's cross-platform and will work with most operating systems (Windows, Mac, Linux). TunerStudio MS is currently the only tuning software than supports the MS3 processor and newer versions of the MS2/Extra firmware. There is both a paid and free version of TunerStudio MS.
SymTech Labs currently recommends TunerStudio MS for tuning your SymTech Labs MegaSquirt ECU.
MegaTune
MegaTune was once the standard software for tuning MegaSquirt ECU's, but it has recently become deprecated. It does not support any of the MS2/Extra 3.x.x+ or MS3 firmware. It is compiled for Windows only. MegaTune is available free of charge.
MegaTunix
MegaTunix offers fewer features than MegaTune and TunerStudio MS, but it is still being actively developed. It offers 3D mapping and custom dashboards. It is available pre-compiled for Linux and Windows, and it can be compiled for Mac OSX. MegaTunix is open source software and is available free of charge.
PalmTune
PalmTune allows you to tune MS1 based ECU's on your Palm. PalmTune is open source software.
PalmTune2
PalmTune2 allows you to tune MS2 based ECU's on your Palm. PalmTune2 is open source software.
MegaLogViewer MS
MegaLogViewer MS allows you to view and replay MegaSquirt logs. Similar to TunerStudio MS, MegaLogViewer MS is cross-platform and runs on all major operating systems. If installed, this program can be accessed directly from TunerStudio MS.
Shadow Logger MS
Shadow Logger MS can capture logs and display data in real-time on any Android 2.1+ device, including phones and tablets. It connects to MegaSquirt logs via Bluetooth, and it is compatible with MS1, MS2, and MS3 MegaSquirt ECU's. Captured are compatible with TunerStudio MS and MegaLogViewer MS.
PalmLog
PalmLog is an open source logger and log viewing utility for PalmOS.
Shadow Dash MS
Similar to Shadow Logger MS, Shadow Dash MS can capture logs and display data in real-time on any Android 2.2+ device, including phones and tablets. It also connects to MegaSquirt logs via Bluetooth, and it is compatible with MS1, MS2, and MS3 MegaSquirt ECU's. Shadow Dash MS supports multiple dashboards and HUD mode, among other features. Captured are compatible with TunerStudio MS and MegaLogViewer MS.
EasyTherm
EasyTherm is utility for calibrating non-GM temperature sensors (such as the factory 420A/Neon sensors) for MS1.