In the short run, there would be survivable problems. In the long run, it would have little effect.
UV is dangerous because it creates free radicals in the outer layers of skin (or leaves or paint or whatever.) Those free radicals are very reactive and attack most materials. The free radical attacking DNA is the route that UV causes skin cancer and more generally the cells reacting to the free radical attacking most organics causes the inflammation of sunburn.
The immediate effect of the loss of ozone would be a major increase in skin cancer and serious problems for animals without fir or feathers (like us) i direct sunlight.
Nonetheless, this can all be adapted to and life would evolve to live in the high-UV environment. There are several ways this can happen.
First, UV doesn't penetrate very deeply and a thicker layer of dead cells on the skin would have good protective power. Shells, fur, feathers all help and would evolve to be thicker.
Second, an increase in free radical scavengers -- chemicals which preferentially react with free radicals yielding harmless products -- would quickly evolve. All animals and plants have some now, so selection for an increase would happen pretty quickly. These scavengers are frequently dark colored, so animals in general might move towards darker hues.
Thirdly, improved repair mechanisms would evolve. DNA mutates a lot and we already have very effective mechanisms to repair those mutations. There's not a lot of evolutionary pressure to improve them now, because must cancers strike after we're don raising a family, so there's not much of a selection effect. In a higher cancer environment, there's certainly be some improvements evolving. This would be slower, though.
Finally there'd be behavioral adaptations: More nocturnal animals, for instance.
Plants likewise would evolve better coping mechanisms.
How fast the ozone loss happens would have a major impact: If it's essentially instantaneous, there'd be no time to evolve better defenses and there'd be a substantial impact until evolution had a chance to operate. In general the impact would be greatest for things with long lifetimes and slow reproduction: Trees for instance might be very hard hit if the decline was quick. People lacking technology might have trouble surviving a quick decline. Me, I'd buy some SPF 100 sunscrean and wear a hat and proper UV-absorbing glasses and try to stay out of the sun.
But life would persist and evolve -- it's good at that. (Though times would be tough for a while, and I'd expect to see a significant impact on longevity.)
As far as the color of the sky goes, the effect would be negligible. The sky is blue because of Raleigh Scattering and ozone is uncolored so it's not clear there's be any noticeable visual effect. You might detect the odor of ozone formed by the UV at ground level.