New features in DaCalc v1.7.1.0

The new version of DaCalc 1.7.1.0 comes with several new features.

1. Automatically use the last result as the first operand if an operator is the first input in normal mode. For example, after calc an expression, 2+3, we get 5 as the result. Now the expression box is empty and user press a + button directly, the last result 5 will be added as the first operand and the expression looks like: 5+. If there is no last result, 0.0 will be added.
2. Minus sign is supported. Now user can press - to add a minus sign before an operand. The following expression is supported now: -5+3
   In order to add the last result for -, user need to long press the - button.
3. The default n-th of a root operator is a Square root. In the earlier version, the n-th of a root operator can not be omitted. It must be written as x√y. Now if the n-th (x) is absent, the operator will be recognized as a Square root operator. It is easier for some common usage.
   It can be downloaded from Android Market now.