Apple's (AAPL) iPhone was again the company's star in the first three months of the year. The tech giant sold 61 million iPhones, or 40 percent more than in the same period a year ago. That represented about two-thirds of its $58 billion in revenue. But executives also shed some light on other well-known Apple products in interviews and a conference call with analysts Monday evening. Apple's tablet computing device, once a red-hot consumer gadget, has suffered from a steady decline in sales over the last year. Apple sold 12.6 million iPads in the latest quarter, for about $5.4 billion in revenue. That's down from 16.3 million iPads sold in the same period a year earlier. At a time when market researchers say the personal computer market is shrinking, Apple is actually increasing its sales of Macs. The company sold 4.6 million Mac desktops and notebook computers in the last quarter. That's a lot fewer than the estimated 13.4 million PCs sold by leading PC-maker Lenovo in the same period. But the Mac contributed $5.6 billion of Apple's revenue last quarter and saw unit sales grow 10 percent, while market researchers at International Data Corp. estimate total PC sales by all vendors shrank nearly 7 percent.