Based on a corpus of voice message narratives in German WhatsApp group chats, the present study contributes to research on social media storytelling in that it focusses on stories of personal experience which are embedded in a communication platform which favours a continuous dialogic exchange, narrated to well-defined non-anonymous publics and multimodal (comprised of visual and audible posting types). To capture the characteristics of this type of social media storytelling, the paper argues that Ochs and Capps’ (2001) dimensional model originally developed for conversational narratives (including the dimensions of tellability, tellership, embeddedness, linearity, moral stance) should be expanded by the dimensions of publicness, multimodality and sequencing. The prototype of storytelling in WhatsApp group chats is based on recent personal experiences; it is related by a single teller as an initial, sequentially non-embedded and linearly organised “big package” story (in a single voice message sometimes introduced by a text message containing an abstract); other group members routinely document their evaluative stances in rather conventionalised text message responses in the semi-public group space.