Join the NitroPress Ambassador Program

Social Media Influencer

United Kingdom

Callum Coles is the creative force behind Calls Cocktails, a popular social media brand dedicated to making homemade cocktails simple, accessible, and delicious. Passionate about mixology and the art of crafting drinks, Callum focuses on easy-to-follow recipes that anyone can recreate at home - no fancy bar tools or rare ingredients required. His goal is to inspire people to enjoy great cocktails with minimal effort, whether they’re entertaining friends or relaxing after a long day.

With a genuine love for flavour, creativity, and sharing experiences, Callum combines his cocktail expertise with his adventurous lifestyle. He’s an avid traveller, car enthusiast, skier, and runner.

Through Calls Cocktails, Callum aims to build a community of cocktail lovers who appreciate simplicity, quality, and the joy of discovery, one delicious drink at a time.

Coffee Specialist

United States

Alex Gren is a passionate and self-taught home barista who has turned a love for coffee into an art form. With a deep appreciation for the craft behind every cup, Alex explores the full spectrum of home brewing, ranging from dialing in espresso shots and mastering milk texture to experimenting with pour-over techniques and alternative brewing methods.

Driven by curiosity and a desire to understand coffee at every level, Alex has built a home setup that rivals professional cafes, constantly testing beans, grinders, and gear to fine-tune the perfect cup. Beyond brewing, Alex shares tips, techniques, and insights to inspire others to elevate their own coffee rituals.

Master mixologist

United Kingdom

Charles is a specialty coffee and cocktail professional with a background in some of London’s top bars and hotels. Originally from the Midwest US, Charles made his way through high-end restaurants before joining teams at Callooh Callay, The Savoy, and Lyaness. His signature style blends classic technique with modern flair — and he’s a huge believer in elevating drinks through texture.