It is legal to keep a phone powered on while operating your vehicle as long as it doesn't interfere with your ability to drive.

PO Box, APO/FPO, Alaska/Hawaii, Albania, Algeria, Andorra, Angola, Bahrain, Barbados, Belize, Benin, Bolivia, Bosnia and Herzegovina, Botswana, British Virgin Islands, Brunei Darussalam, Burkina Faso, Burundi, Cambodia, Cameroon, Cape Verde Islands, Central African Republic, Chad, China, Colombia, Comoros, Cook Islands, Côte d'Ivoire (Ivory Coast), Democratic Republic of the Congo, Djibouti, Dominican Republic, Ecuador, Egypt, El Salvador, Equatorial Guinea, Eritrea, Ethiopia, Fiji, France, French Guiana, French Polynesia, Gabon Republic, Gambia, Georgia, Germany, Ghana, Gibraltar, Greenland, Guadeloupe, Guam, Guatemala, Guernsey, Guinea, Guinea-Bissau, Honduras, Hong Kong, India, Indonesia, Jamaica, Jersey, Jordan, Kazakhstan, Kenya, Kuwait, Lebanon, Lesotho, Liberia, Libya, Madagascar, Malawi, Mali, Martinique, Mauritania, Mauritius, Mayotte, Morocco, Mozambique, Namibia, New Caledonia, Nicaragua, Niger, Nigeria, Oman, Palau, Panama, Papua New Guinea, Paraguay, Puerto Rico, Qatar, Republic of the Congo, Reunion, Russian Federation, Rwanda, Saint Helena, Saint Lucia, Saint Pierre and Miquelon, Saint Vincent and the Grenadines, Senegal, Seychelles, Sierra Leone, Somalia, Sri Lanka, Suriname, Swaziland, Taiwan, Tanzania, Togo, Trinidad and Tobago, Tunisia, Turkey, US Protectorates, Uganda, Ukraine, Vanuatu, Venezuela, Virgin Islands (U.S.Ideally, you want to place your phone somewhere that's visible, and you can quickly press buttons and respond to alerts if necessary.

Phone pocket holder