# Data viewer list causes app to slow down **URL:** \ **Category:** Questions about Thunkable X\ **Created:** [April 25, 2022, 7:20am UTC](https://community.thunkable.com/t/data-viewer-list-causes-app-to-slow-down/1846748 "2022-04-25T07:20:48Z")\ **Posts on this page:** 1\ **Showing post:** 2
**Author:** ![tatiang](https://sea1.discourse-cdn.com/flex015/user_avatar/community.thunkable.com/tatiang/32/55482_2.png) [@tatiang](https://community.thunkable.com/u/tatiang)\ **Post date:** [April 25, 2022, 7:39am UTC](https://community.thunkable.com/t/data-viewer-list-causes-app-to-slow-down/1846748/2 "2022-04-25T07:39:50Z")
Without knowing more, I’m going to assume the API has nothing to do with this and the button’s functionality has nothing to do with this. So you’re saying that a DVL with 20 or more rows causes buttons on the same screen to respond slowly regardless of the code used for those buttons? How many columns does your data source have? And how many columns are you displaying at once in each DVL row? Can you provide a link to a project that demonstrates this behavior? You might be interested in this recent topic: > [@DataViewerList speed testing](https://community.thunkable.com/t/dataviewerlist-speed-testing/1841281): > > Hello Thunkers ! Sometimes an application needs to dynamically build, populate and display a local table on the screen. And I noticed that doing so, DVL become slow in showing results. So I made a simple app to exemplify that, building a table with only 30 rows/9 columns with no other beautify than changing every row color. And still for that it requires more than 10 seconds to display it (on a real fast phone, a Qualcomm Snapdragon 888 Octa-core RealMe GT edition). This is the link to app, … --- _[View the full topic](https://community.thunkable.com/t/data-viewer-list-causes-app-to-slow-down/1846748)._