My env:
iPhone 6s with iOS 11.1.2, Xcode 9.1 (9B55)
WebDriverAgent master code from Nov 20, 2017
Symptoms:
The /wda/tap end point is not performing correctly when the app is in the landscape mode.
Taps are being applied only to a certain limit of the X-coordinate. It feels like the coordinates
are internally filtered by the bounding box of the portrait application (375x667).
The issue is not new to the latest iOS 11.1.2. I had the same problem about 2 months ago with an older WDA version and the initial iOS 11 release.
Steps to reproduce:
- Start the iBooks application
- Rotate the device to the landscape left mode
- Select the "My Books" screen (see the screen shot)
- Tap "Most Recent" at [180,50] -> the tap performs correctly
- Tap "Authors" - the tap gets applied only if x<375
- No taps with x>=375 are possible - no way to tap for example "Categories" or "Select"

The log:
$ export JSON_HEADER='-H "Content-Type: application/json"'
$ curl -X POST $JSONHEADER -d "{"desiredCapabilities":{"bundleId":"com.apple.iBooks"}}" http://192.168.1.8:8100/session
{
"value" : {
"sessionId" : "1D07CE20-34DA-4F86-9B66-FFC96739C9AD",
"capabilities" : {
"device" : "iphone",
"browserName" : "iBooks",
"sdkVersion" : "11.1.2",
"CFBundleIdentifier" : "com.apple.iBooks"
}
},
"sessionId" : "1D07CE20-34DA-4F86-9B66-FFC96739C9AD",
"status" : 0
}
Tap “Most Recent” - SUCCESSFUL
$ curl -X POST $JSONHEADER -d "{"x":180,"y":50}" http://192.168.1.8:8100/session/1D07CE20-34DA-4F86-9B66-FFC96739C9AD/wda/tap/0
{
"value" : {
},
"sessionId" : "1D07CE20-34DA-4F86-9B66-FFC96739C9AD",
"status" : 0
}
Tap “Categories” - UNSUCCESSFUL, TAP NOT APPLIED
$ curl -X POST $JSONHEADER -d "{"x":490,"y":50}" http://192.168.1.8:8100/session/1D07CE20-34DA-4F86-9B66-FFC96739C9AD/wda/tap/0
{
"value" : {
},
"sessionId" : "1D07CE20-34DA-4F86-9B66-FFC96739C9AD",
"status" : 0
}