Both bathrooms have cracked grout where the tile meets the tub. They were done by a contractor 2.5 years ago. The second picture shows a crack going away from the tub between tiles.
This bathroom has hairline cracks.
This bathroom cracks thicker than a hairline.
Should I just put new grout over the cracks and press it in the cracks? Should I grind out the grout entirely and start fresh? Are there any special patch up products? I have never worked with grout before and I am clueless as to the best strategy.