MUG: Interactive Multimodal Grounding on User Interfaces
Tao Li, Gang Li, Jingjie Zheng, Purple Wang, Yang Li
TL;DR
Mug introduces an interactive multimodal grounding task for mobile UIs, enabling iterative user-agent collaboration on a single screen. A large dataset (77,820 sequences across 7,132 apps) supports both offline and online evaluation, including human and automatic user models. The authors implement a Transformer-based UI encoder and a causal grounding decoder, and explore multiple agent and user model variants, including imitation and offline RL approaches. Results show that allowing multi-turn interaction substantially improves task completion (18% overall, 31% on challenging cases) and reveal robustness challenges that motivate future improvements in grounding, user modeling, and evaluation. The work provides a solid benchmark and demonstrates the value of interactive grounding for realistic UI understanding and accessibility scenarios.
Abstract
We present MUG, a novel interactive task for multimodal grounding where a user and an agent work collaboratively on an interface screen. Prior works modeled multimodal UI grounding in one round: the user gives a command and the agent responds to the command. Yet, in a realistic scenario, a user command can be ambiguous when the target action is inherently difficult to articulate in natural language. MUG allows multiple rounds of interactions such that upon seeing the agent responses, the user can give further commands for the agent to refine or even correct its actions. Such interaction is critical for improving grounding performances in real-world use cases. To investigate the problem, we create a new dataset that consists of 77,820 sequences of human user-agent interaction on mobile interfaces in which 20% involves multiple rounds of interactions. To establish our benchmark, we experiment with a range of modeling variants and evaluation strategies, including both offline and online evaluation-the online strategy consists of both human evaluation and automatic with simulators. Our experiments show that allowing iterative interaction significantly improves the absolute task completion by 18% over the entire test dataset and 31% over the challenging subset. Our results lay the foundation for further investigation of the problem.
