HubSpot CRM - Free CRM software for small businesses.
Telegram - Telegram is a messaging app with a focus on speed and security. It’s superfast, simple and free.
Keap - Grow Sales. Save Time. Get Organized.
Skype - Stay in touch with your family and friends for free on Skype. Download Skype today to chat and call on desktop and mobile.
Less Annoying CRM - A simple customer relationship manager made just for small businesses. Manage contact info, track leads, and never miss a follow-up.
WhatsApp - WhatsApp Messenger: More than 1 billion people in over 180 countries use WhatsApp to stay in touch with friends and family, anytime and anywhere.