All-in-one Shower Gel
Some people have suggested that it would be great if one could buy a shampoo and shower gel all-in-one, if not to simplify things while travelling. As it turns out, one can buy such a product here. As shampoo, I find it works better than the stand-alone shampoo leftover in my new apartment:
Looking at the ingredients, it seemed like most shower gels and shampoos were pretty similar. Some ingredients were there in different proportions. The all-in-one products actually seemed to have better items included in the ingredient lists, such as the tea tree oil in the product I purchased.