The service designed for building conversational agents capable of voice and text interactions is Lex. It uses advanced deep learning to offer automatic speech recognition (ASR) and natural language understanding (NLU), allowing the creation of applications with highly interactive user experiences. SageMaker is more suited to general machine learning model development and training; Kendra provides enterprise search powered by machine learning, and DeepLens is a deep learning-enabled video camera for developing and deploying machine learning models.