For solo developers working on latency-sensitive applications, Fly.io is the better choice. Its true multi-region deploys ensure low latency for users, and the scale-to-zero feature helps keep costs manageable during idle times. However, be prepared for a steeper learning curve and variable billing based on usage, which might not suit those seeking predictable costs.
On the other hand, if you value ease of deployment and minimal infrastructure management, Railway is ideal. It offers a straightforward Git-push workflow, making it perfect for indie hackers who want to focus on building rather than managing. However, the lack of a permanent free tier and the potential for rising costs due to usage might deter those who need cost predictability or more control over deployment regions.