You create a canvas mobile app using SharePoint lists (Equipment and Sales) as data sources. 
You want to improve the app’s performance. 
Please select all the delegable statements.

Answer options:

A.Collect(LocalEquipment, TextInput1.Text)
B.Filter(Equipment,ID=2346)
C.Concat(Sales,Title & ",")
D.LookUp(Sales,Title="Mango",UnitsSold)

Correct Answers: B and D 
For the best performance of a canvas app, you need to consider the following tips: Limit data connections — no more than 30 data sources for the same app.
Limit the number of controls — no more than 500 controls per app.
Effective OnStart load — for data load use in a parallel process by implementing the Concurrent function.
Optimize local caching — use the Set function for local caching.
Load screens in memory only when needed — avoid screen dependencies and formula sharing between screens.
Use delegation — process data close to the source, on the data server, as much as you can. Use predominantly delegable functions.
Republish your app regularly — Power Platform adds new features all the time that can help your app’s performance.
When working with a large dataset, you need to limit the number of records you can bring to the client. 
By default, the Power Apps limits the number of records that you can bring to 500. You can change this limit in the app`s settings. But if your result set from the data operation would be over this limit, Power Platform will download only the limited number of records. 
Therefore, push the data-heavy operations` execution on the back end of your data source. Power Apps provides functions that are optimized to perform such actions. These functions are called delegable functions. 
Execution of these functions depends on the delegation support by the data source. The delegable data sources include Common Data Service, SharePoint, SQL Server, and some others. The list of the delegable functions consists of a filter (like Filter, Search, and Lookup), sorting (Sort and SortByColumns), aggregate (Sum, Average, Min, and Max), and table shaping (like AddColumns, DropColumns, etc.) functions. The list of non-delegable functions includes Collect, Concat, Choices, Groupby, etc. 
When a connector does not support the function delegation, App Checker will let you know. Even the Sum function (Number 1) is on the list of potential delegable functions, but the SharePoint connector does not support this functionality. And App Checker issues the Delegation warning (Number 2). 

Options B and D are correct because Filter and Lookup are the delegable functions and supported by the SharePoint connector.
Options A and C are incorrect because Collect and Concat are non-delegable functions.
For more information about the canvas app’s delegation and performance optimization, please visit the below URLs: 

https://docs.microsoft.com/en-us/powerapps/maker/canvas-apps/delegation-overview
https://docs.microsoft.com/en-us/powerapps/maker/canvas-apps/common-performance-issue-resolutions
https://docs.microsoft.com/en-us/connectors/sharepointonline/#power-apps-delegable-functions-and-operations-for-sharepoint