The Mother in Law's Tongue (Sansevieria) is also called a Snake
plant. It is considered a sub-
succulent and should always be watered sparingly but regularly, especially in the winter when they are more or less dormant. The variegated forms enjoy full sun but can tolerate some shade. The burned tips could possibly be caused from overwatering, but very likely resulted from the rapid change in environment.
When your houseplants are moved outdoors, it is very important to acclimatize them gradually. For the first couple days let them stay in a shaded area, then move them into increasingly brighter spots, until they have adjusted to full sun (7-10 days)... That is, of course, only if they are full sun
plants!
Sansevierias seem to thrive and
flower best when they are kept somewhat rootbound. They appreciate an occasional sponge bath!