The document discusses the functionality and capabilities of Microsoft PowerApps, focusing on creating apps with offline support and integration with on-premises data. It covers various features such as using Excel-like formulas, customizing SharePoint forms, and implementing data connection strategies. Key findings highlight the importance of performance optimization, adaptive design for different screen sizes, and recent enhancements to the platform.

1. Enterprise PowerApps – Rich Apps
with Offline Support and On-
Premises Data
Chris O’Brien (MVP)
Independent/Content and Code

3. Use Excel-like formulas – not code
To do Formula
“Next” button to change screen Navigate(MyScreen, ScreenTransition.Fade)
Add item to SharePoint list Patch(MySharePointList, Defaults(MySharePointList),
{
FirstName:TextInput1.Text,
LastName:TextInput2.Text
}
)
Add record to local collection
(cache)
ClearCollect(
SelectedProducts,
{
ID: ProductID,
Name: ”XT1000”
}
)

4. Not required

5. The mobile experience
PowerApps app must be installed from App
Store
Apps appear within the PowerApps app

6. Types of
PowerApps
Canvas apps
Model-driven apps
Customised
SharePoint list forms

7. Customising SP forms vs. canvas apps
Customised SP forms:
Other considerations:

8. CASE STUDY APP
Pilot/crew leave requests

9. The scenario
POC for airline pilots (leave requests)
Flying a plane is the perfect time!
Offline support
Ability to connect to on-
premises data

10. DEMO – Leave
Requests
PowerApp

11. Flow

12. Implementing the PowerApp
Key findings
Some surprises

13. Functions for SharePoint data
Patch
• Add list item
Collect
• Fetch list item
Update
• Update list item
Delete
• Remove
Multi-page forms
Person/Group fields
Taxonomy fields

14. A Patch command in our app

15. A Patch command in our app (formatted)

16. Implementing offline support
Pattern
Poll for local
record –
LoadData/ForAll
PATCH if
connected
Navigate to
confirmation
screen

17. On-premises data gateway
Considerations

18. Working with data
Connection is hit when:
Data-related functions:
Connection (e.g.
a database)
Data source
(e.g. a table)

19. Using a Gallery control for navigation
The pattern
On start - define
collection of screens
(with ClearCollect)
Gallery OnSelect -
lookup screen from
selected item, then
navigate

20. DEMO –
Implementing
offline and
integrating data

21. PowerApps tips
Performance, key functions, responsive apps

22. Tips – key PowerApps functions
To do Use
Set a global variable available across all screens Set()
Set a context variable in a single screen UpdateContext() – and also Navigate()
Change screen Navigate(), Back()
Save a local record (e.g. for offline) Collect(), ClearCollect(), Update – use SaveData() to store
Open a web address/app Launch()
Get data on current user User()
Display a message banner Notify()
150+ functions in total. See:
https://docs.microsoft.com/en-
us/powerapps/formula-reference

23. Tips
Get used to:
Lots of fiddly work to generate PATCH command 
Adding a “debug screen” with labels showing variables etc
“Declarative” variables
Variables and If statements
NOT:OnLoad-If(X){Label1.Visible=true}else{Label1.Visible=false}
INSTEAD:Label1.Visible=if(X,false,true)
Conditional display
Adda“rule”tocontrol,usepaneltoconfigurewhatpropertieswhichshouldbeset(e.g.Visible=false)

24. Be careful loading data sources
Tips - performance
https://powerapps.microsoft.com/en-
us/blog/tips-for-a-maintainable-extensible-app
https://powerapps.microsoft.com/en-
us/blog/performance-considerations-with-
powerapps/
Consider not loading OnStart (slow app load)
Load into local collections and consume those
Use Concurrent() if appropriate (e.g. multiple data sources)
Using a Connector? Avoid multiple trips to the server

25. Tips - using PATCH with SharePoint fields
To do Use
Update a choice/lookup from a dropdown Paternity_LengthOfPaternityLeave: {
'@odata.type':"#Microsoft.Azure.Connectors.
SharePoint.SPListExpandedReference",
Value: ddlPaternityLeaveDuration.Selected.Value,
Id: 1
}
Update a person field currentUser: {
'@odata.type':"#Microsoft.Azure.Connectors.
SharePoint.SPListExpandedUser",
Claims:"i:0#.f|membership|" & Lower(User().Email),
Email:User().Email,
JobTitle:".",
Picture:"."
}

26. Responsive canvas apps
Adapt to screen size – not just phone/tablet choice
+ -

27. PowerApps
- the good

28. PowerApps
- the bad

29. PowerApps
- the ugly

30. My favourite recent/upcoming features
Available or in preview
• PowerApps web part in SharePoint!
• New size/layout options - choose size OR
use responsive (with formulas)
• Improved performance – parallel data load,
faster SharePoint forms
• App checker
• ALM – solution export/import
• Up to 20MB offline storage
• Message panel (Notify function)
Jan 2019
• Better debugging – e.g. in middle of formula
(Jan 2019)
• Easier cascading dropdowns (Jan 2019)
• Friendly SharePoint names in formulas

31. Takeaways
PowerApps can be VERY transformative for an org with lots of forms/processes
Very easy to get apps onto mobile devices
“Simple” requirements can sometimes be
difficult to implement
1
2
3
4 PowerApps are going to continue to evolve!

32. Resources
https://cob-sp.com/PowerAppsVideos
https://cob-sp.com/2QjvG5y
https://powerapps.microsoft.com/en-
us/blog/

33. Thank you!! 
Any questions?
www.sharepointnutsandbolts.com
@ChrisO_Brien