  Mobile applications play an important role in the economy today and there is
an increasing trend for app enablement on multiple platforms. However,
creating, distributing, and maintaining an application remain expert tasks.
Even for software developers, the process can be error-prone and
resource-consuming, especially when targeting different platforms
simultaneously. Researchers have proposed several frameworks to facilitate
cross-platform app development, but little attention has been paid to
non-technical users. In this paper, we described the Flow framework, which
takes the advantage of domain-specific languages to enable no-code
specification for app modeling. The cloud-native coordination mechanism further
supports non-technical users to execute, monitor, and maintain apps for any
target platforms. User evaluations were conducted to assess the usability and
user experience with the system. The results indicated that users can develop
apps in Flow with ease, but the prototype could be optimized to reduce learning
time and workload.
