# SEMA3: A free smartphone platform for daily life surveys

## TL;DR

SEMA3 is a free smartphone platform that helps researchers collect daily life data through repeated surveys on Android and iOS devices.

## Contribution

SEMA3 introduces a free, flexible, and user-friendly platform for administering intensive longitudinal surveys via smartphones.

## Key findings

- SEMA3 supports both basic and advanced features for designing daily life surveys.
- The platform addresses a gap in accessible tools for intensive longitudinal research.
- The paper outlines SEMA3's architecture, functionality, and future development directions.

## Abstract

Traditionally, behavioral, social, and health science researchers have relied on global/retrospective survey methods administered cross-sectionally (i.e., on a single occasion) or longitudinally (i.e., on several occasions separated by weeks, months, or years). More recently, social and health scientists have added daily life survey methods (also known as intensive longitudinal methods or ambulatory assessment) to their toolkit. These methods (e.g., daily diaries, experience sampling, ecological momentary assessment) involve dense repeated assessments in everyday settings. To facilitate research using daily life survey methods, we present SEMA3 (http://www.SEMA3.com), a platform for designing and administering intensive longitudinal daily life surveys via Android and iOS smartphones. SEMA3 fills an important gap by providing researchers with a free, intuitive, and flexible platform with basic and advanced functionality. In this article, we describe SEMA3’s development history and system architecture, provide an overview of how to design a study using SEMA3 and outline its key features, and discuss the platform’s limitations and propose directions for future development of SEMA3.