Starbucks Tip App Sparks Tipping Questions That We Answer

Starting next week, you'll be able to tip Starbucks baristas with the coffee chain's mobile iPhone app, but

how much of a gratuity, if any, should you leave? Deciding who gets tipped and how much is more complicated than ever, so read on for some tips on what to do.

First off, those hard-working Starbucks baristas do depend on tips, but it's entirely up to you. The Emily Post Institute, named after the legendary advice columnist, says customers aren't under any obligation to tip baristas, unlike the way social norms dictate one should tip a restaurant waiter.

Read More: 50 Cents, $1 or $2? Starbucks Adding Digital Tips

If they go out of their way to help you or provide a great level of service or courtesy, Daniel Post Senning, great-great-grandson of Emily Post and author and spokesman for the Emily Post Institute in Burlington, Vt., says you almost can't go wrong in tipping a service professional.

The Emily Post Institute offers general suggestions for tipping, based on historical precedence. But there are some industries that aren't considered traditional tipping services in the eyes of many.

While Post Senning doesn't have a suggestion for occupations such as full-service gas station attendants or tailors, that doesn't mean you should refrain from giving something to them.

"I would never tell someone not to tip if they felt inspired," he said. "That's what a gratuity is, to show they're thankful."

He adds that a genuine verbal expression of gratitude can go a long way, and sometimes might even go further than disrespectfully throwing money at someone.

"Saying that or leaving a little note is a meaningful gesture," he said.

Social norms tend to guide individuals in tipping for services that are more intimate, such as personal grooming.

Post Senning includes in that category home services, such as house-cleaning or driveway plowing. And it's usually a nice gesture if you tip service professionals, such as au pairs, private nurses, pet groomers, more during the holidays, the Institute advises. Tipping in certain professions, such as doctors and teachers, might be frowned upon, but non-cash gifts in those cases are usually appreciated, Post Senning said.

In case some people, cultures or businesses might be offended at a tip or lack thereof, the Emily Post Institute says it doesn't hurt to ask about guidelines. And tipping "discreetly," the Institute says, is "classy."

Here are some more tipping guidelines from the institute:

News Source: abcnews.go.com