They can also use the app offline, by saving reports and later uploading them when back in cell phone range.
Police senior constable Tony Maw said it is similar to the Snap Send Solve app used by some district councils in the Canterbury region.
"If we don't know about it, it's not happening," he said.
"If we can see there is a problem, then we're in a position to do something about it."
The most frequent crimes highlighted are illegal hunting and poaching, followed by property theft and slaughtering or theft of livestock.
However, a police survey revealed rural crime was largely unreported nationally.
Maw said this was a factor in about 80 per cent of rural incidents.
"We've discovered it's not just fuel theft, but it's also hunting and trespassing."
He said there had been some investigation of the barriers preventing community members from reporting incidents.
The app will not "replace" standard services including 111 for emergencies or the 105 online service.
"They are still really important channels," Maw said.
"It's just another reporting channel."
In addition, the trial will use "geospatial capability" to create a rural crime dashboard for the area.
All reported crime and suspicious activity will be mapped on the dashboard.
Police unveiled the app and programme trial to Waimakariri Mayor Dan Gordon and Hurunui Mayor Marie Black last month.
Gordon said the community has been concerned about a gradual rise in rural crime.
"It's great to see the Police looking at new ways to equip farmers to report rural crime and be involved in combating this rise," he said.
"I'd strongly encourage everyone in our rural communities to download this app and use it to report suspicious activity and help play a part in making our rural areas safer."
An increase in crime has also been felt further north in the Hurunui district.
Black said the app will provide a direct link between rural residents and the police.
"As a large rural district, I often hear farmers talk about the rise of rural crimes like fuel theft and poaching and how it affects them.
"I think the functionality will also help in how quickly police can respond and start investigating these crimes."
