The 28-year-old was out of contract at the Iron, who he captained to the play-off semi-final this season, where they lost to eventually-promoted Grimsby.
He joined from Grays in 2010 and leaves following the departure of Iron manager Danny Cowley to Lincoln.
Davis' new side finished 19th in their first-ever season in non-league's top flight last campaign.

The worst-affected areas were in the Midlands, where roads flooded, rail passengers were stranded and many schools closed.
About 50 Environment Agency flood warnings - meaning "immediate action required" - are currently in place.
More than 160 lower-level flood alerts have been issued across much of England and parts of Wales.
Flooding continues to cause severe disruption on some roads, including sections of the A428 and A3400 in Warwickshire.
BBC forecaster Tomasz Schafernaker said Thursday's weather would be a "lot quieter", with "none of that heavy rain that we had first thing in the morning on Wednesday".
He said cloud would clear overnight, leaving a "few spots of rain" in central and eastern England by Thursday morning, with clear skies and low temperatures elsewhere.
On Wednesday, British Transport Police formed human barriers to hold back crowds at London Euston after trains between Rugby and Milton Keynes were cancelled.
In Warwickshire, 14 schools were closed and a number of people were rescued from cars by firefighters due to floodwater.
In Birmingham, a man was filmed using a ladder as a bridge to reach a van which was stranded.

It had lost its mother and become stranded in shallow waters off the coast of Mojacar in Andalucia.
Tourists then began touching and photographing the animal rather than seeking help for it.
Equinac, a local NGO, said "selfishness" caused the dolphin "suffering and stress."
The organisation, which works to protect marine wildlife in the area, wrote in a Facebook post (in Spanish): "The animal was subjected to the curious who wanted to photograph and touch it."
"These animals are highly protected; to disturb them, to harm them, to manipulate them and to harass them is prohibited by law, and we always ask for respect and consideration."
Boreham Wood have signed midfielder Kenny Davis from National League rivals Braintree Town on a one-year deal.
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Dozens of flood warnings remain in place in central England following heavy rain and disruption on Wednesday.
[NEXT_CONCEPT]
A baby dolphin has died after it was surrounded by tourists looking to take photographs on a beach in southern Spain.