In the year 2011 I was in the search for free programming solutions for the STM32 Discovery boards when I found the Atollic True Studio Lite. It was a very interesting product. Based on Eclipse, it provided all the necessary tools to develop on ARM MCUs. It had some functionality limitations in the free version but It was very good for learning and teaching MCU programming.
That ended at the start of 2012 when Atollic decided to set at 32KB code limit in True Studio Lite. When programming a STM32F4 Discovery board that features 1MB of flash, a code limit of 32KB is a joke. Moreover, it made impossible to integrate an RTOS and some middleware in the code. As I was using ChibiOS at this time, this limitation was very important to me. I complained to Atollic, but, in the end, I found that I was out of the user group that Atollic was targetting. So, I moved on, leaved Atollic alone, and developed my own Eclipse based environment and used it for learning and teaching. That was dificult because the debug was quite difficult to setup at that time and ChibiOS didn't had come with ChibiStudio yet.
Now, at the end of 2015, almost four years after Atollic introduced the code limit in True Studio Lite, Atollic has decided to remove it. That is good news because ST provides examples for True Studio for its evaluation boards so it eases a lot the developement. Perhaps it is time to check again what Atollic has to offer but now there are quite more free options to develop in ARM MCUs that there were at the start of 2012. And now I have my own toolchain.
But for anyone willing to program the cheap evaluation boards that ST and others like Freescale provide, Atollic True Studio Lite is a free solution that should be taken into account now that the code limit is removed.