flutter app not taking full width of ipad screen?

Question

launching the app on android and iPhones works well while launching it on iPad the app unexpectedly is not taking the full width of the screen!

tried editing the Main.storyboard <view> width but nothing occurs

<view key="view" contentMode="scaleToFill" id="8bC-Xf-vdC">
    <rect key="frame" x="0.0" y="0.0" width="600" height="600"/>
    <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
    <color key="backgroundColor" white="1" alpha="1" colorSpace="custom" customColorSpace="calibratedWhite"/>
</view>

Solution 1

You need to register your app Universal

Go to Runner > Target > Deployment info

Solution 2

In the newest XCode version it's not the same anymore as an accepted answer, now you can do it like this.

1. Go to Runner/BuildSettings and find Deployment

2. Click on the iPhone next to Targeted Device Families and then on other

3. In the box add 2 and press enter

And that's it. It will look like this now: