cell9 has released NTR Debugger, which lets you debug Homebrew on retail 3DS’s, here is a quote from the source:
NTR Debugger v1.0.0
1 You have to hold on power button until power led is off to shutdown your console when the debugger is actived.
2 Works on emunand with fw 4.5 only, if your firmware version on emunand > 4.5, you should format the emunand using the original gw loader.
This tool allows your read/write kernel memory, which could cause hardware damage.Use at your own risk.
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