You may have noticed a few of your friends "checking in" on Facebook to somewhere pretty far away: Standing Rock, North Dakota, USA.
The posts are in support of demonstrators who are trying to block a 1,200-mile pipeline which will span four states and crosses Native American Sioux tribe land.
So what's it all about and are the "check-ins" helping?
What are the demonstrators protesting over?
The Standing Rock Sioux tribe claims that a planned 3.8 billion dollar (£3.1 billion) pipeline from North Dakota to Illinois will threaten its drinking water and destroy sacred sites.
Protests which have included clashes with police have gone on since March at the reservation in North Dakota and have grown increasingly fractious. This weekend more than 140 people were arrested at the site of the protest.
The company building the pipeline, Energy Transport Partners, argues that the pipeline is a safer way of transporting oil over road and rail and will provide jobs.
The Sioux Indians, like many tribes across the US, made a land deal with the government in 1851 when the different states were formed. They claim the land which the pipeline is being built on is theirs under this treaty, which they say the US government has dishonoured.
Why is everyone checking in on Facebook, then?
Activists have expressed concerns that their organising activities are being monitored on social media by police.
As a reaction to this, an unknown account posted a call to arms asking Facebook users to "check in" at Standing Rock in order to confuse law enforcement about who was attending and prevent them from targeting individuals in the crowd.
The post has been shared thousands of times and to date, 1.4 million people have "checked in" to Standing Rock and the surrounding area.
Many are also leaving "reviews" for the area, quoting the same block of text in support of the protesters.
"I stand in solidarity with your struggles of oppression. I hope your strife ends soon and with no more blood shed. Water is life and should be considered a human right especially for those that have been victim to major genocide in the past.
"I hope that one day human decency is restored and we can all live as one. I hope that we no longer bow down to the corporate enterprises that have deceived this country and stolen our freedom in exchange of profits and materialistic want.
"May we be guided by the great spirit in defeating those that are intent on harming the great mother earth. Love and peace to those in the trenches of the great mother earth. Love and peace to those in the trenches.
"Calling on the Creator to love and protect our loved ones from harms way in this battle, may peace be with us all and the battle end in our favor. #Waterislife"
So did it work?
The jury is out on that one. The local police department issued a statement on its Facebook page to say it was not tracking people through Facebook check-ins anyway.
However, the main camp supporting the protest said the check-ins had brought welcome publicity to the cause, but also urged supporters to take "physical action" as well.
The practice of checking in may not have been an effective tool to confuse law enforcement.
If police were indeed monitoring people's whereabouts, geolocation data, showing where a person's phone actually was when a post was made rather than looking at straightforward "check-ins" would be a more effective method.
How else can I show my support?
The Stand with Standing Rock website suggests three ways you can help, if you'd like. You can sign the petition, which already has over 94,000 signatures, call the White House to register your opinion, or donate to the cause.
What's happening now?
The federal government has temporarily halted construction along the disputed section of land, and Barack Obama has said army engineers are examining whether the Dakota Access oil pipeline can be rerouted through southern North Dakota to alleviate the concerns of Native Americans.
Obama said his administration is monitoring the situation closely but will "let it play out for several more weeks".