This book constitutes the refereed proceedings of the 12th International Conference on Artificial Intelligence and Mobile Services, AIMS 2023, Held as Part of the Services Conference Federation, SCF 2023, Honolulu, HI, USA, September 23-26, 2023. The 9 full papers presented together and selected from 16 submissions. The conference focuses on AI modeling; AI analysis; AI & mobile applications; AI architecture; AI management; AI engineering; mobile backend as a service (MBaaS); and user experience of AI & mobile services.