BillKaro runs your whole shop from your phone. Make GST tax invoices (CGST/SGST/IGST) or a simple Bill of Supply in seconds, print on a 58/80mm Bluetooth thermal printer, and share bills on WhatsApp. Track customer udhaar with WhatsApp reminders, supplier dues, stock with barcode scan & low-stock alerts, and daily sale/profit reports. Hindi & English, cloud backup. Free on Android, Pro from Rs.25/month.