The No. 1 trait single daters are prioritizing next year is trustworthiness, according to Tinder's Year in Swipe end-of-year report.

It's obvious why daters want a partner they can trust, what is more opaque is how to find one.

It can take a few months to unearth someone's character. Sometimes, though, you can tell pretty early if a person isn't reliable and honest, says Devyn Simone, a dating expert at Tinder.

"You know how they say 'If I win the lottery I won't say anything, but there will be signs,'" Simone says. "Generally, there are certain signs."

Here are three red flags that could indicate your date isn't trustworthy.

1. Their dating profile has one photo

"If they have just one photo I'd say it's a no-go," Simone says. "If my 70-something-year-old father can have a handful of photos on social media then anyone can have more than one photo."

A person who doesn't put effort into their profile is "not thoughtful," Simone says, as they aren't considering what the experience is like for those swiping on them. You don't want to put your trust in someone who isn't thinking about others from the start.

Even if they have more than one photo, be sure the pictures are clear. Not being able to see their face or body might indicate they are trying to hide something.

"There are so many people on the app," Simone says. "You don't have to settle for the one who is like a jigsaw puzzle."

2. They don't text when they say they will

When someone is a slow texter or less responsive than you'd like, it's easy to excuse it, especially if you don't know them very well yet.

But if they make a point to tell you that they will contact you by a certain time and don't, this is probably a sign of their unreliability.

"Even something as simple as saying, 'I'll message you after I get off work,' [make sure] that they actually do that and that it's not three days later," she says.

3. They change plans last minute

It's hard to feel comfortable or safe with another person if they are constantly in flux about what they want to do.

"If anyone leaves you in limbo where they say they want to do one thing then they all of a sudden want to do something else, that is a bad sign," she says.

You should feel confident that the plan they laid out will actually happen.

Learn to trust yourself

Sometimes our being slow to trust people has nothing to do with their actions, and is based on our own lived experiences. This isn't always a bad thing, says Lisa Bobby, a relationship psychologist and founder of Growing Self Counseling & Coaching in Denver.

"I think it's wise to be cautiously optimistic," she says. "We don't want to assume other people are malevolent liars, but you really shouldn't trust people you don't know very well."

Remind yourself that character reveals itself over time.

"When we get too attached to the idea of somebody before we know who they are it impairs our ability to see them," Bobby says. "We are observing them through a filter."

If you've felt romantically misled and are finding it hard to trust again, it might be helpful to analyze your own blind spots. To do this, Bobby says you can ask yourself a few questions:

• What was I telling myself about this person that was ultimately incorrect?
• What are my patterns and my vulnerabilities?
• If I had to do this over again, what should I have been looking for or paying attention to?

The answers are usually illuminating, Bobby says: "I've never met a person who, when we did that exploration, didn't have some lapses on their side that could have protected them."

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