Panasonic GF5 has a Micro Four Thirds lens mount and currently there are 125 native lenses available for this mount.
The latest released lenses that are compatible with the GF5 are the Rokinon 7.5mm f3.5 Fisheye, the Samyang 7.5mm F3.5 Fisheye MFT and the OM SYSTEM 9-18mm f4.0-5.6 II.
Panasonic GF5 doesn't have a sensor based image stabilization system but
37 of these lenses already comes with optical image stabilization.
Since Panasonic GF5 has a Four Thirds sensor, it has a focal length multiplier of 2× so you have to multiply lenses original focal length with this multiplier to find the Full Frame equivalent focal length of the lens when mounted on GF5.
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Panasonic GF5 Lenses with Image Stabilization
Panasonic GF5 Lenses with Weather Sealings