What’s the best way to show a user that a field is tappable?

I have an Android application that displays information row by row. Like below

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Field                         Value

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Field                         Value

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Field                         Value

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Some of the rows can be tapped to display more information in the form of an Android Toast. I was wondering what the best way to inform the user that some of the rows are tappable. My first thought was to display an exclamation mark on the row, but it doesn't necessarily make sense for an exclamation mark to be there.

Thoughts?

Thanks for all the help, it's appreciated