There's no difference in meaning. Boh mean "in". 裡 is just the traditional chinese character and 里 is the simplified chinese character. There's actually an even older version, 裏.

ps: traditional Chinese is widely used in Hongkong, Taiwan, etc, while simplified Chinese is used in the mainland of China. Suggest u to learn simplified Chinese.. easier. more practical.

i'm agree with @terry&Cherry ,but they both means "in",for example:I'm in here(我在这里), I'm trying to tell you something about Chinese...^-^.