One should use caution when using a cell phone as a sex toy as research is showing that they may cause cancer. In addition, they are known for harboring bacteria which can easily lead to a urinary tract infection (UTI).

As for remotes, they should not be used as a sex toy as they may contain phthalates (a known toxin banned in children's toys).

There are two helpful articles that you should read-

1) This article discusses homemade sex toys and what you should know before using them-

2) This article reviews what toxins can be found in some sex toys and personal lubricants and how to avoid them and choose sex toys that are safe and nontoxic-