Before revision:  We leveraged prior work regarding receptivity to JITAIs and deployed a chatbot-based digital coach  -- Walkie -- that provided physical-activity interventions and motivated participants to achieve their step goals.
After revision:  We leveraged prior work regarding receptivity to JITAIs and deployed a chatbot-based digital coach ~ -- Walkie -- that provided physical-activity interventions and motivated participants to achieve their step goals.