Interacting with Large Language Models (LLMs) for text editing on mobile devices currently requires users to break out of their writing environment and switch to a conversational AI interface. In this paper, we propose to control the LLM via touch gestures performed directly on the text. We first chart a design space that covers fundamental touch input and text transformations. In this space, we then concretely explore two control mappings: spread-to-generate and pinch-to-shorten, with visual feedback loops. We evaluate this concept in a user study (N=14) that compares three feedback designs: no visualisation, text length indicator, and length + word indicator. The results demonstrate that touch-based control of LLMs is both feasible and user-friendly, with the length + word indicator proving most effective for managing text generation. This work lays the foundation for further research into gesture-based interaction with LLMs on touch devices.
View on arXiv@article{zindulka2025_2502.07629,
title={ Exploring Mobile Touch Interaction with Large Language Models },
author={ Tim Zindulka and Jannek Sekowski and Florian Lehmann and Daniel Buschek },
journal={arXiv preprint arXiv:2502.07629},
year={ 2025 }
}