Power Apps app loads slowly — how to speed it up
A Power Apps app loads slowly or feels laggy mainly because App.OnStart runs too much work before the app can render, filters aren’t delegable, or the same data source gets queried repeatedly. Immediate fix: move non-essential logic out of OnStart into each screen’s OnVisible, load only what the first screen needs, and use Concurrent() to run independent data loads in parallel instead of sequentially. Durable fix: replace ClearCollect of large tables with delegable queries fetched on demand, keep filters delegable so the server processes rows instead of pulling 500-2000 rows locally, and set DelayOutput on text inputs to avoid re-querying on every keystroke.
Trim App.OnStart
- 1Move work out of OnStart: it blocks the app from loading until it finishes.
- 2Load only what the first screen needs; defer the rest to each screen’s OnVisible.
- 3Replace ClearCollect of large tables with delegable queries that fetch on demand.
Cut the number of data calls
- 1Avoid calling the same source repeatedly — store the result once in a variable or collection.
- 2Use Concurrent() to run independent data loads in parallel instead of one after another.
- 3Set DelayOutput on text inputs so each keystroke doesn’t re-query.
Keep queries delegable
Non-delegable filters pull up to 500–2000 rows into the app and process them locally — slow and incomplete. Make filters delegable so the server does the work (see the delegation guide).