Also, have you tried reuploading the firmware update? Or tried uploading the firmware you had previous to 2v15?
EDIT: Or maybe, uninstall bootloader and install it again.
Tried all nothing seems to help, default apps works 100% but adding an app or widget let me not boot again.
@user133055 started
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
Also, have you tried reuploading the firmware update? Or tried uploading the firmware you had previous to 2v15?
EDIT: Or maybe, uninstall bootloader and install it again.