user20059: According to the chess app I am using, this is not a checkmate against black:
[FEN "1rk4r/1p6/3p3q/Q1pPbRnP/p1P3B1/P6P/1P4R1/7K w - - 0 1"]

1. Rf7+

How is it not? I think the black king is checkmated by the queen and the white-squared bishop.

user12523: It is not checkmate because Black can interpose a piece to block the check from the bishop: move knight or queen to e6.
It's still only a miniscule delay for the inevitable.
[FEN "1rk4r/1p6/3p3q/Q1pPbRnP/p1P3B1/P6P/1P4R1/7K w - - 0 1"]

1.Rf7+ Ne6
(1...Qe6 2.Qc7#)
2.Qc7# 1-0


20059: <p>According to the chess app I am using, this is not a checkmate against black:</p>

<pre><code>[FEN "1rk4r/1p6/3p3q/Q1pPbRnP/p1P3B1/P6P/1P4R1/7K w - - 0 1"]

1. Rf7+
</code></pre>

<p>How is it not? I think the black king is checkmated by the queen and the white-squared bishop.</p>
 12523: <p>It is not checkmate because Black can interpose a piece to block the check from the bishop: move knight or queen to e6.</p>

<p>It's still only a miniscule delay for the inevitable.</p>

<pre><code>[FEN "1rk4r/1p6/3p3q/Q1pPbRnP/p1P3B1/P6P/1P4R1/7K w - - 0 1"]

1.Rf7+ Ne6
(1...Qe6 2.Qc7#)
2.Qc7# 1-0
</code></pre>
