I heard that in New Hampshire apple store they don't add tax. Is that correct?

Yup, no sales tax in NH, now if you're a MA resident, don't forget now you must pay the sales tax along with your MA income tax, but nobody in NH will care one way or the other and you won't get charged. You can even buy liquor in the NH liquor stores and bring bottles into MA but again, you MUST pay MA the 6.5% tax. Hmm... look for NH tax amnesty day where you as a MA or Maine resident gets a double sales tax discount. https://www.boston.com/news/local-news/2018/08/09/new-hampshire-liquor-wine-discount-coupon

No sales taxes here in NH.

There is no sales tax in NH.