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On the window in Step 2, specify the Page which is an editable drop-down (best practice is to use application name followed by “_” and followed by page name, for example myApp_login, myApp_search, etc.) and Alias for the locator you are defining along with only one unique identifier. This identifier can be the ID, Name or Partial Text. You can also choose XPath instead of Identifier.
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By default, Common option is enabled where the Identifier or XPath is the same across platforms, but you can switch to “Platform-specific” to enter values unique to iOS and Android.
Click the Save & Close button to save your locator. Once saved, your newly defined locator will show up in the locator listing on the Mobile Locators screen.