Tips for Mobile Access development and run time

These are general tips for developing projects for Mobile Access, as well as for using the Mobile Access web interface during run time.

Make sure that you do not use unsupported features

Mobile Access currently supports many but not all features of InduSoft Web Studio. If you use an unsupported feature in a project screen, you might see unexpected behavior when you view that screen in the Mobile Access web interface. Such behavior can range from incorrect tag changes and function calls to objects, animations, or scripts that do not work at all.

Make sure that all of the screen objects, animations, background tasks, VBScript, and built-in functions that you use are included in the list of supported features. For more information, see List of features supported in project screens in Mobile Access.

If you do use unsupported features, they will be reported in the Output Window in the development environment when you either verify your project or publish your screens as HTML.

Make sure you are using an HTML5-compatible browser

To use the Mobile Access web interface, you must have a modern, HTML5-compatible web browser. Different browsers have different levels of support for HTML5, however, and many older browsers do not support it at all. This can cause a wide variety of issues, from project screens not behaving as expected to the entire web interface not opening at all.

Therefore, the first thing you should do whenever you have issues with Mobile Access is make sure that you are using an HTML5-compatible browser, preferably one that we have validated for use with Mobile Access:
Table 1. List of validated browsers
Platform Browser
Windows Phone 8 Internet Explorer (default browser)
Android Gingerbread (version 2.3.x) Android Browser (default browser)
Note: Alarm, Process Values, and Trend controls only; Screens are not supported on this browser.
Android Ice Cream Sandwich (version 4.0.x) Chrome for Android
Android Jelly Bean (versions 4.1, 4.2, 4.3) Chrome for Android
iOS 6 (version 6.1.x) Safari (default browser)
iOS 7 (version 7.0.x) Safari (default browser)
Windows, Linux, Mac OS X Internet Explorer 11
Google Chrome
Safari (version 5.x or later)

For more information, see Log on to the Mobile Access web interface.

Make sure your computer or device has enough resources

Viewing large or complex project screens in the Mobile Access web interface can be resource-intensive, and your computer or device might not have enough resources (e.g., processor, memory, bandwidth) to do the job regardless of how new it is, which operating system it runs, or which browser you use. If either the web interface in general or a specific project screen seems to perform unsatisfactorily, try viewing it on another computer or device. Also, particularly on mobile devices like smartphones and tablets, check to see if your device’s battery is low or if you have other apps open. Any or all of these factors can affect the performance of the web interface and give you a false impression of Mobile Access itself.

If, after checking these things, you still see unsatisfactory performance, you may need to “lighten” your project screens — that is, modify your screens to decrease the amount of resources that they require. Here are a few ways to do that:
  • Try not to use large, high-resolution pictures in a screen, especially if you resize them in the screen editor after you place them. Replace them wherever possible with pictures that are properly scaled and resampled. Also, try decreasing the image resolution (e.g., from 300 DPI to 72 DPI) if full resolution is not necessary.
  • Do not to paste a picture or use a group of objects more than once in a screen, because each instance requires its own resources. Replace these pictures and groups with Linked Pictures and Linked Symbols, respectively.
  • Make sure the project screen itself is properly sized for the computers or devices on which you plan to view it. It is a waste of resources to create, for example, a 2560-by-1440 screen for a 1136-by-640 smartphone. The screen is automatically scaled to fit the browser in which it is viewed, so nothing will be inadvertently cropped or hidden, and the user can zoom into a scaled screen to see smaller details, if necessary. (Please note that zooming works somewhat differently in mobile browsers versus desktop browsers.) An oversized screen, however, always takes more resources and is more difficult to use.

    You can change the screen size in the Screen Attributes.

In the end, however, please keep in mind that the performance of the Mobile Access web interface is not an indicator of the performance of the InduSoft Web Studio project runtime itself. Regardless of what you see in your browser, your project should be running well everywhere else.

Other tips for developing for Mobile Access

Here are some other tips for project and screen development:
Do not enable file compression
In projects that are accessed by Secure Viewer and Web Thin Client, you can choose to compress the screen files to make them faster to download over slow connections. (The option Enable File Compression is located on the Web tab of the project settings. For more information, see Web tab.) This feature is not supported in Mobile Access. If you try to view a project screen that has been compressed like this, the screen might behave unexpectedly and you might see messages in the activity log that say tags or objects do not exist.
Avoid tag synchronization when opening screens
If you use a large number of project tags in the VBScript sub-routines Screen_OnOpen or Graphics_OnOpen, your screens might take a long time to open or update. This is because the tag values — even for project tags with Local scope — must be synchronized between server and client when the scripts are executed, and that can take a long time if you have a slow client/server connection.

The solution is to use VBScript variables instead of project tags wherever possible. Variables exist only within the scripts where they are declared and used, so no synchronization is required. Otherwise, you can check the activity log to see which tags are being synchronized and when.

Do not use “Executed on Server” functions in FOR loops
Similar to the issue of tag synchronization that is described above, if you use a large number of functions marked “Executed on Server”, your project screens might take a long time to update. This is because the function calls must be sent from the client to the server, and then the returned values must be sent from the server to the client.

This is especially true of functions called from within a FOR loop. The loop itself can be executed relatively quickly on the client, but the function calls might “stack up” as the client waits for the server to execute them.

If you experience any of the issues described above, you can use the activity log to troubleshoot your project screens. For more information, see Troubleshooting project screens in Mobile Access.

Tips for development and run time