  We present high sensitivity HI observations of NGC 6822, obtained with the
Karoo Array Telescope (KAT-7). We study the kinematics, the mass distribution,
and the star formation thresholds. The KAT-7 short baselines and low system
temperature make it sensitive to large-scale, low surface brightness emission.
The observations detected $\sim$ 23$\%$ more flux than previous ATCA
observations. We fit a tilted ring model to the HI velocity field to derive the
rotation curve (RC). The KAT-7 observations allow the measurement of the
rotation curve of NGC 6822 out to 5.8 kpc, $\sim$ 1 kpc further than existing
measurements.
  NGC 6822 is seen to be dark matter dominated at all radii. The
observationally motivated pseudo-isothermal dark matter (DM) halo model
reproduces well the observed RC while the Navarro Frank-White DM model gives a
poor fit to the data. We find the best fit mass to light ratio (M/L) of 0.12
$\pm$ 0.01 which is consistent with the literature. The Modified Newtonian
Dynamics (MOND) gives a poor fit to our data.
  We derive the star formation threshold in NGC 6822 using the HI and H$\alpha$
data. The critical gas densities were calculated for gravitational
instabilities using the Toomre-Q criterion and the cloud-growth criterion. We
found that in regions of star formation, the cloud-growth criterion explains
star formation better than the Toomre-Q criterion. This shows that the local
shear rate could be a key player in cloud formation for irregular galaxies such
as NGC 6822.
