Lens mount: OM Bayonet
Shutter: Focal plane, 1~1/2000 + B
Meter: Dual CdS center or spot-weighted, OTF TTL in aperture priority mode
Viewfinder: split-image focus dot, LCD shutter speed display
Battery: LR44 x2
Sold for $770 (1986), $1800 (2020)
Purchased for $182 w/ 1.8 50mm, 1.4 50mm (2020)
+1/200 shutter speed
+Shutter Speed indicator in viewfinder
+Compatibility with all accessories in OM lineup
-Marginally more weight (510g OM-4ti vs 520g OM-2)
This was it, the final iteration of the OM series. It in many ways has intersections with the OM-2S with the addition of a handy spot meter and viewfinder readout additions. One of my lingering criticisms of the OM-2 was the lack of aperture/shutter speed readouts in the viewfinder, one cameras like the Minolta XD included in a very legible manner. It did make for a very simple, quick, and compact camera, but that addition would've been nice. The OM-4 also released around the same time as the OM-3, a now very desirable variant with a mechanically-controlled shutter. If you find one for under $300, grab it immediately.
Shutter speeds on the OM-4ti have also been increased by one stop to 1/2000. A very welcome feature for shooting wide open, although mechanical cameras like the FM2 did manage 1/4000 with a vertical plane shutter. Like every camera since the OM-2n, it has the option to shoot in aperture priority. Weathersealing is also a unique feature with this camera, although your lenses will still be vulnerable to dust and rain.
Why not buy an OM-4 or an OM-2s for ~$70 instead of something like this? Functionally, there's not a huge discrepancy. I went for the titanium version for the clout and it makes for a lighter camera, thematically consistent with the OM ideology. I also purchased it in a bundle with two other lenses, so I got some of my money back through reselling too.
Considering this was a $1000+ camera in the early 2000's, I'm very happy with it. It's the apogee of Olympus' film days and my god is it enjoyable.
It's not a linear upgrade from the OM-2. The extra capabilities are welcome to a platform that was always a bit behind the times, but they come at a cost of a dimmer viewfinder.