Many firmware developers of CC2541 BLE SoC are familiar with IAR toolchain. Although IAR is a very good compiler and IDE to work with, it only comes with a free 30-days evaluation license - afterward a regular paid license is required. To some developers, especially electronics makers, students, and small design houses, toolchain with no upfront cost for building their prototypes and applications is their primary concern.
On this front, TI has made a great decision to make their new CC26xx SoC platform to support both IAR and their owned Code Composer Studio (CCS) toolchain that the latter comes with a free license as long as a XDS compatible JTAG debugger is used. You can follow this link to download the free CCS toolchain, and this link to download the latest BLE stack to start your development.
As for XDS compatible JTAG debuggers, both XDS100 and XDS110 debuggers are very affordable – especially the XDS110 DevPack debugger which costs only $15 plus shipping from TI Store.