Question: when did smart phones first hit the market
[{'answer': '1999', 'provenance': [{'wikipedia_id': '167079', 'title': 'Smartphone', 'start_paragraph_id': 11, 'start_character': 8, 'end_paragraph_id': 11, 'end_character': 12, 'bleu_score': 1.0, 'section': 'Section::::History.:PDA/phone hybrids.\n'}]}]