Live view lets you take photos without using the viewfinder which makes you less obstrusive and this works very well during street photography where you don't want to get people's attention. Face-Detection Focusing
Face detection focusing mode is very helpful in the street scenes where you focus on a face, since you can concentrate on framing and other adjustments while the camera handles the focus for you. Tilting LCD Screen
An articulated screen gives you the flexibility to shoot in non traditional positions such as waist level, which helps you to be more creative and unobtrusive in the streets. Image Stabilization
Image stabilization reduces the effects of camera shake at long exposures and long focal lengths in street photography thus ensuring sharper photos. 21 mm - Good Wide Angle Coverage
Having a good wide angle coverage becomes very important in street photography. Small Body
Small body of Olympus TG-870 will get less attention from the people in streets and give you an amateur look, which is indeed an advantage for street photography.
No Built-in Viewfinder
In the lack of a a viewfinder, holding the camera away from the body while using live view is not very stable, especially with heavy camera bodies and lenses. Besides, LCD screens are very hard to read under bright sunlight. No Manual Focus Mode
In street photography, things changes very quickly and often you may not have enough time to frame and focus at the right time to catch the moment. Zone focusing is a popular technique amongst street photographers and it requires manual focus mode. No RAW shooting capability
JPEG files are generally more attractive direct out of the camera but RAW files contains much more color information compared to JPEGs, and gives you more room for post processing without significant quality loss. They provide wider dynamic range and option to recover shadow and highlight clipping to some degree. Small 1/2.3" (6.17 x 4.55 mm) sensor
Olympus TG-870's small sensor struggles in low light situations compared to larger sensors.